IOS#App Library

{{See also|iOS version history}}

In 2005, when Steve Jobs began planning the iPhone, he stated that he had a choice to either "shrink the Mac, which would be an epic feat of engineering, or enlarge the iPod". Jobs favored the former approach but pitted the Macintosh and iPod teams, led by Scott Forstall and Tony Fadell, respectively, against each other in an internal competition, with Forstall winning by creating iPhone OS. The decision enabled the success of the iPhone as a platform for third-party developers: using a well-known desktop operating system as its basis allowed the many third-party Mac developers to write software for the iPhone with minimal retraining. Forstall was also responsible for creating a software development kit for programmers to build iPhone apps, as well as an App Store within iTunes.{{cite web |first1=Adam |last1=Satariano |first2=Peter |last2=Burrows |first3=Brad |last3=Stone |title=Scott Forstall, the Sorcerer's Apprentice at Apple |url=https://www.bloomberg.com/news/articles/2011-10-12/scott-forstall-the-sorcerers-apprentice-at-apple |website=Bloomberg Businessweek |publisher=Bloomberg L.P. |date=October 14, 2011 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170407032342/https://www.bloomberg.com/news/articles/2011-10-12/scott-forstall-the-sorcerers-apprentice-at-apple |archive-date=April 7, 2017 }}{{cite web |first=Arnold |last=Kim |title=Scott Forstall's Personality, Origins of iOS, and Lost iPhone 4 Prototype |url=https://www.macrumors.com/2011/10/13/scott-forstalls-personality-origins-of-ios-and-lost-iphone-4-prototype/ |website=MacRumors |date=October 12, 2011 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081118/https://www.macrumors.com/2011/10/13/scott-forstalls-personality-origins-of-ios-and-lost-iphone-4-prototype/ |archive-date=April 2, 2017 }}

The operating system was unveiled with the iPhone at the Macworld Conference & Expo on January 9, 2007, and released in June of that year.{{cite web |first=Owen |last=Thomas |title=Apple: Hello, iPhone |url=https://money.cnn.com/2007/01/09/technology/apple_jobs/ |website=CNN Money |publisher=CNN |date=January 9, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081508/http://money.cnn.com/2007/01/09/technology/apple_jobs/ |archive-date=April 2, 2017 }}{{cite magazine |first=Lisa |last=Eadicicco |title=Watch Steve Jobs Unveil the First iPhone 10 Years Ago Today |url=https://time.com/4628515/steve-jobs-iphone-launch-keynote-2007/ |magazine=Time |date=January 9, 2017 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402080922/http://time.com/4628515/steve-jobs-iphone-launch-keynote-2007/ |archive-date=April 2, 2017 }}{{cite web |first=Mathew |last=Honan |title=Apple unveils iPhone |url=http://www.macworld.com/article/1054769/smartphones/iphone.html |website=Macworld |publisher=International Data Group |date=January 9, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170126161949/http://www.macworld.com/article/1054769/smartphones/iphone.html |archive-date=January 26, 2017 }} At the time of its unveiling in January, Steve Jobs claimed: "iPhone runs OS X" and runs "desktop class applications",{{cite web |first=Ryan |last=Block |author-link=Ryan Block |title=Live from Macworld 2007: Steve Jobs keynote |url=https://www.engadget.com/2007/01/09/live-from-macworld-2007-steve-jobs-keynote/ |website=Engadget |publisher=AOL |date=January 9, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170324084725/https://www.engadget.com/2007/01/09/live-from-macworld-2007-steve-jobs-keynote/ |archive-date=March 24, 2017 }}{{cite web |first=Mic |last=Wright |title=The original iPhone announcement annotated: Steve Jobs' genius meets Genius |url=https://thenextweb.com/apple/2015/09/09/genius-annotated-with-genius/ |website=The Next Web |date=September 9, 2015 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401232647/https://thenextweb.com/apple/2015/09/09/genius-annotated-with-genius/ |archive-date=April 1, 2017 }} but at the time of the iPhone's release, the operating system was renamed "iPhone OS".{{cite web |title=iOS: A visual history |url=https://www.theverge.com/2011/12/13/2612736/ios-history-iphone-ipad |website=The Verge |publisher=Vox Media |date=September 16, 2013 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170412015548/http://www.theverge.com/2011/12/13/2612736/ios-history-iphone-ipad |archive-date=April 12, 2017 }} Initially, third-party native applications were not supported. Jobs' reasoning was that developers could build web applications through the Safari web browser that "would behave like native apps on the iPhone".{{cite web |first=Antone |last=Gonsalves |title=Apple Launches iPhone Web Apps Directory |url=http://www.informationweek.com/apple-launches-iphone-web-apps-directory/d/d-id/1060220 |website=InformationWeek |publisher=UBM plc |date=October 11, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170220092434/http://www.informationweek.com/apple-launches-iphone-web-apps-directory/d/d-id/1060220 |archive-date=February 20, 2017 }}{{cite web |title=Jobs' original vision for the iPhone: No third-party native apps |url=https://9to5mac.com/2011/10/21/jobs-original-vision-for-the-iphone-no-third-party-native-apps/ |website=9to5Mac |date=October 21, 2011 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401233112/https://9to5mac.com/2011/10/21/jobs-original-vision-for-the-iphone-no-third-party-native-apps/ |archive-date=April 1, 2017 }} In October 2007, Apple announced that a native software development kit (SDK) was under development and that they planned to put it "in developers' hands in February".{{cite web |first=Nik |last=Fletcher |title=Apple: "we plan to have an iPhone SDK in developers' hands in February" |url=https://www.engadget.com/2007/10/17/apple-we-plan-to-have-an-iphone-sdk-in-developers-hands-in-fe/ |website=Engadget |publisher=AOL |date=October 17, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402080846/https://www.engadget.com/2007/10/17/apple-we-plan-to-have-an-iphone-sdk-in-developers-hands-in-fe/ |archive-date=April 2, 2017 }}{{cite web |first=Daniel |last=Eran Dilger |title=Nine Years of Apple's iOS SDK generated $60 billion, 1.4 million jobs |url=http://appleinsider.com/articles/17/03/07/nine-years-of-apples-ios-sdk-generated-60-billion-14-million-jobs |website=AppleInsider |date=March 7, 2017 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081011/http://appleinsider.com/articles/17/03/07/nine-years-of-apples-ios-sdk-generated-60-billion-14-million-jobs |archive-date=April 2, 2017 }}{{cite web |first=Philip |last=Elmer-DeWitt |title=Steve Jobs: Apple Will Open iPhone to 3rd Party Apps in February |url=http://fortune.com/2007/10/17/steve-jobs-apple-will-open-iphone-to-3rd-party-apps-in-february/ |website=Fortune |date=October 17, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402080842/http://fortune.com/2007/10/17/steve-jobs-apple-will-open-iphone-to-3rd-party-apps-in-february/ |archive-date=April 2, 2017 }} On March 6, 2008, Apple held a press event, announcing the iPhone SDK.{{cite web |first=Ryan |last=Block |author-link=Ryan Block |title=Live from Apple's iPhone SDK press conference |url=https://www.engadget.com/2008/03/06/live-from-apples-iphone-press-conference/ |website=Engadget |publisher=AOL |date=March 6, 2008 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170127165446/https://www.engadget.com/2008/03/06/live-from-apples-iphone-press-conference/ |archive-date=January 27, 2017 }}{{cite web |first1=Jim |last1=Dalrymple |first2=Jason |last2=Snell |title=Apple: iPhone SDK, enterprise announcement next week |url=http://www.macworld.com/article/1132275/sdk.html |website=Macworld |publisher=International Data Group |date=February 27, 2008 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081039/http://www.macworld.com/article/1132275/sdk.html |archive-date=April 2, 2017 }}

File:Apple iPhone 2G 8GB (16).jpg (2007), the first commercially released device running iOS, then called iPhone OS]]

The iOS App Store was opened on July 10, 2008, with an initial 500 applications available.{{cite web |first=Thomas |last=Ricker |title=Jobs: App Store launching with 500 iPhone applications, 25% free |url=https://www.engadget.com/2008/07/10/jobs-app-store-launching-with-500-iphone-applications-25-free/ |website=Engadget |publisher=AOL |date=July 10, 2008 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330012936/https://www.engadget.com/2008/07/10/jobs-app-store-launching-with-500-iphone-applications-25-free/ |archive-date=March 30, 2017 }} This quickly grew to 3,000 in September 2008,{{cite web |title=App Store Downloads Top 100 Million Worldwide |url=https://www.apple.com/pr/library/2008/09/09App-Store-Downloads-Top-100-Million-Worldwide.html |website=Apple Press Info |publisher=Apple Inc. |date=September 9, 2008 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401111744/http://www.apple.com/pr/library/2008/09/09App-Store-Downloads-Top-100-Million-Worldwide.html |archive-date=April 1, 2017 }} 15,000 in January 2009,{{cite web |first=Rik |last=Myslewski |title=iPhone App Store breezes past 500 million downloads |url=https://www.theregister.co.uk/2009/01/16/half_billion_iphone_apps/ |website=The Register |publisher=Situation Publishing |date=January 16, 2009 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170505165333/http://www.theregister.co.uk/2009/01/16/half_billion_iphone_apps/ |archive-date=May 5, 2017 }} 50,000 in June 2009,{{cite web |first=MG |last=Siegler |title=State Of The iPhone Ecosystem: 40 Million Devices and 50,000 Apps |url=https://techcrunch.com/2009/06/08/40-million-iphones-and-ipod-touches-and-50000-apps/ |website=TechCrunch |publisher=AOL |date=June 8, 2009 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20090610235745/http://www.techcrunch.com/2009/06/08/40-million-iphones-and-ipod-touches-and-50000-apps/ |archive-date=June 10, 2009 }} 100,000 in November 2009,{{cite web |first=Dan |last=Moren |title=App Store officially passes 100,000 app mark |url=http://www.macworld.com/article/1143641/appstore_100000.html |website=Macworld |publisher=International Data Group |date=November 4, 2009 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330013112/http://www.macworld.com/article/1143641/appstore_100000.html |archive-date=March 30, 2017 }}{{cite web |first=Dan |last=Frommer |title=iPhone App Store Passes 100,000 Apps |url=http://www.businessinsider.com/iphone-app-store-passes-100000-apps-2009-11 |website=Business Insider |publisher=Axel Springer SE |date=November 4, 2009 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330000058/http://www.businessinsider.com/iphone-app-store-passes-100000-apps-2009-11 |archive-date=March 30, 2017 }} 250,000 in August 2010,{{cite web |first=Matt |last=Brian |title=Apple's App Store Now Features 250,000 Apps |url=https://thenextweb.com/mobile/2010/08/28/apples-app-store-now-features-250000-apps/ |website=The Next Web |date=August 28, 2010 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170329233606/https://thenextweb.com/mobile/2010/08/28/apples-app-store-now-features-250000-apps/ |archive-date=March 29, 2017 }}{{cite web |first=Philip |last=Elmer-DeWitt |title=Apple App Store: 250,000 and counting |url=http://fortune.com/2010/08/28/apple-app-store-250000-and-counting/ |website=Fortune |date=August 28, 2010 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330000653/http://fortune.com/2010/08/28/apple-app-store-250000-and-counting/ |archive-date=March 30, 2017 }} 650,000 in July 2012,{{cite web |first=Jordan |last=Crook |title=Apple App Store Hits 650,000 Apps: 250,000 Designed For iPad, $5.5B Paid Out To Devs |url=https://techcrunch.com/2012/07/24/apple-app-store-hits-650000-apps-250000-designed-for-ipad-5-5b-paid-out-to-devs/ |website=TechCrunch |publisher=AOL |date=July 24, 2012 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330014047/https://techcrunch.com/2012/07/24/apple-app-store-hits-650000-apps-250000-designed-for-ipad-5-5b-paid-out-to-devs/ |archive-date=March 30, 2017 }} 1 million in October 2013,{{cite web |first=Nathan |last=Ingraham |title=Apple announces 1 million apps in the App Store, more than 1 billion songs played on iTunes radio |url=https://www.theverge.com/2013/10/22/4866302/apple-announces-1-million-apps-in-the-app-store |website=The Verge |publisher=Vox Media |date=October 22, 2013 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170512171633/https://www.theverge.com/2013/10/22/4866302/apple-announces-1-million-apps-in-the-app-store |archive-date=May 12, 2017 }}{{cite web |first=Seth |last=Fiegerman |title=Apple's App Store Tops 1 Million Apps |url=http://mashable.com/2013/10/22/apple-app-store-1-million/ |website=Mashable |date=October 22, 2013 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330012049/http://mashable.com/2013/10/22/apple-app-store-1-million/ |archive-date=March 30, 2017 }} 2 million in June 2016,{{cite web |first=Jordan |last=Golson |title=Apple's App Store now has over 2 million apps |url=https://www.theverge.com/2016/6/13/11922926/apple-apps-2-million-wwdc-2016 |website=The Verge |publisher=Vox Media |date=June 13, 2016 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170210135527/http://www.theverge.com/2016/6/13/11922926/apple-apps-2-million-wwdc-2016 |archive-date=February 10, 2017 }}{{cite web |first=Kellen |last=Beck |title=Apple's App Store now has over 2 million apps |url=http://mashable.com/2016/06/13/apple-wwdc-apps/ |website=Mashable |date=June 13, 2016 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330012051/http://mashable.com/2016/06/13/apple-wwdc-apps/ |archive-date=March 30, 2017 }}{{cite web |first=Erin |last=Carson |title=Apple by the numbers: 2 million apps, 15 million Apple Music subscribers |url=https://www.cnet.com/uk/news/apple-by-the-numbers-2-million-apps15-million-apple-music-subscribers10-billion-icloud-documents/ |website=CNET |publisher=CBS Interactive |date=June 13, 2016 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330014530/https://www.cnet.com/uk/news/apple-by-the-numbers-2-million-apps15-million-apple-music-subscribers10-billion-icloud-documents/ |archive-date=March 30, 2017 }} and 2.2 million in January 2017.{{cite web |first=Lauren |last=Goode |title=Apple's App Store just had the most successful month of sales ever |url=https://www.theverge.com/2017/1/5/14173328/apple-december-2016-app-store-record-phil-schiller |website=The Verge |publisher=Vox Media |date=January 5, 2017 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170128232821/http://www.theverge.com/2017/1/5/14173328/apple-december-2016-app-store-record-phil-schiller |archive-date=January 28, 2017 }}{{cite web |first=Larry |last=Dignan |title=Apple's App Store 2016 revenue tops $28 billion mark, developers net $20 billion |url=https://www.zdnet.com/article/apples-app-store-2016-revenue-tops-28-billion-mark-developers-net-20-billion/ |website=ZDNet |publisher=CBS Interactive |date=January 5, 2017 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330055612/http://www.zdnet.com/article/apples-app-store-2016-revenue-tops-28-billion-mark-developers-net-20-billion/ |archive-date=March 30, 2017 }} {{As of|2016|3}}, 1 million apps are natively compatible with the iPad tablet computer.{{cite web |first=Jacob |last=Kastrenakes |title=There are now 1 million iPad apps |url=https://www.theverge.com/2016/3/21/11277804/1-million-ipad-apps |website=The Verge |publisher=Vox Media |date=March 21, 2016 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330011925/http://www.theverge.com/2016/3/21/11277804/1-million-ipad-apps |archive-date=March 30, 2017 }} These apps have collectively been downloaded more than 130 billion times. App intelligence firm Sensor Tower estimated that the App Store would reach 5 million apps by 2020.{{cite web |first=Sarah |last=Perez |title=App Store to reach 5 million apps by 2020, with games leading the way |url=https://techcrunch.com/2016/08/10/app-store-to-reach-5-million-apps-by-2020-with-games-leading-the-way/ |website=TechCrunch |publisher=AOL |date=August 10, 2016 |access-date=March 29, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170330003410/https://techcrunch.com/2016/08/10/app-store-to-reach-5-million-apps-by-2020-with-games-leading-the-way/ |archive-date=March 30, 2017 }}

In September 2007, Apple announced the iPod Touch, a redesigned iPod based on the iPhone form factor.{{cite web |first=Eric |last=Bangeman |title=The iPod meets the iPhone: a review of the iPod Touch |url=https://arstechnica.com/apple/2007/09/the-ipod-meets-the-iphone-a-review-of-the-ipod-touch/ |website=Ars Technica |date=September 17, 2007 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160618215925/http://arstechnica.com/apple/2007/09/the-ipod-meets-the-iphone-a-review-of-the-ipod-touch/ |archive-date=June 18, 2016 }} On January 27, 2010, Apple introduced their much-anticipated media tablet, the iPad, featuring a larger screen than the iPhone and iPod Touch, and designed for web browsing, media consumption, and reading, and offering multi-touch interaction with multimedia formats including newspapers, e-books, photos, videos, music, word processing documents, video games, and most existing iPhone apps using a {{convert|9.7|in|cm|adj=on}} screen.{{Cite web|last=Rose|first=Michael|date=January 27, 2013|title=January 27, 2010: Apple announces the iPad|url=https://www.engadget.com/2013/01/27/january-27-2010-apple-announces-the-ipad/|access-date=April 18, 2017|website=Engadget|publisher=AOL|archive-date=July 16, 2018|archive-url=https://web.archive.org/web/20180716024921/https://www.engadget.com/2013/01/27/january-27-2010-apple-announces-the-ipad/|url-status=live}}{{Cite web|last=Foresman|first=Chris|date=January 27, 2010|title=Apple announces the iPad|url=https://arstechnica.com/apple/2010/01/apple-announces-ipad-attempts-to-change-the-world/|access-date=April 18, 2017|website=Ars Technica|archive-date=April 19, 2017|archive-url=https://web.archive.org/web/20170419103354/https://arstechnica.com/apple/2010/01/apple-announces-ipad-attempts-to-change-the-world/|url-status=live}}{{Cite web|date=January 27, 2010|title=Apple Launches iPad|url=https://www.apple.com/pr/library/2010/01/27Apple-Launches-iPad.html|access-date=April 18, 2017|website=Apple Press Info|publisher=Apple Inc.|archive-date=July 3, 2011|archive-url=https://web.archive.org/web/20110703062209/http://www.apple.com/pr/library/2010/01/27Apple-Launches-iPad.html|url-status=live}} It also includes a mobile version of Safari for web browsing, as well as access to the App Store, iTunes Library, iBookstore, Contacts, and Notes. Content is downloadable via Wi-Fi and optional 3G service or synced through the user's computer.{{cite web|date=January 27, 2010|title=Apple Tablet Media Event Today: "Come See Our Latest Creation"|url=https://www.macrumors.com/2010/01/27/apple-tablet-media-event-today-come-see-our-latest-creation/|access-date=September 4, 2020|website=MacRumors|archive-date=September 20, 2020|archive-url=https://web.archive.org/web/20200920032548/https://www.macrumors.com/2010/01/27/apple-tablet-media-event-today-come-see-our-latest-creation/|url-status=live}} AT&T was initially the sole U.S. provider of 3G wireless access for the iPad.{{Cite web|author=Tony Bradley|date=January 29, 2010|title=AT&T Beefing Up Network for iPad and iPhone|url=https://www.pcworld.com/article/188149/atandt_beefing_up_network_for_ipad_and_iphone.html|url-status=live|archive-url=https://web.archive.org/web/20100201014134/https://www.pcworld.com/article/188149/atandt_beefing_up_network_for_ipad_and_iphone.html|archive-date=February 1, 2010|access-date=January 29, 2010|website=PC World}}

In June 2010, Apple rebranded iPhone OS as "iOS".{{cite web|url=https://www.engadget.com/2010-06-07-iphone-os-4-renamed-ios-gets-1500-new-features.html|title=iPhone OS 4 renamed iOS 4, launching June 21 with 1500 new features|first=N.|last=Patel|date=June 7, 2010|website=Engadget|access-date=June 25, 2022|archive-date=May 23, 2022|archive-url=https://web.archive.org/web/20220523171310/https://www.engadget.com/2010-06-07-iphone-os-4-renamed-ios-gets-1500-new-features.html|url-status=live}}{{cite web|url=https://www.macworld.com/article/205857/iphone_os_4_wwdc.html|title=iPhone OS gets new name, video calling|first=David|last=Chartier|website=Macworld|date=June 7, 2010|access-date=June 25, 2022|archive-date=June 22, 2022|archive-url=https://web.archive.org/web/20220622234009/https://www.macworld.com/article/205857/iphone_os_4_wwdc.html|url-status=live}} The trademark "IOS" had been used by Cisco for over a decade for its operating system, IOS, used on its routers. To avoid any potential lawsuit, Apple licensed the "IOS" trademark from Cisco.{{cite web | last = Tartakoff | first = Joseph | publisher = paidContent | url = http://paidcontent.org/article/419-deja-vu-apples-new-ios-brand-is-already-used-by-cisco/ | title = Apple Avoids iPhone-Like Trademark Battle Thanks To Cisco, FaceTime Deals | date = June 7, 2010 | access-date = February 2, 2011 | url-status=dead | archive-url = https://web.archive.org/web/20110511200002/http://paidcontent.org/article/419-deja-vu-apples-new-ios-brand-is-already-used-by-cisco/ | archive-date = May 11, 2011 | df = mdy-all }}

The Apple Watch smartwatch was announced by Tim Cook on September 9, 2014, being introduced as a product with health and fitness-tracking.{{Cite web|last=Garun|first=Natt|date=September 9, 2014|title=Everything Apple announced at its September 2014 keynote|url=https://thenextweb.com/apple/2014/09/09/everything-apple-announced-september-2014-keynote/|access-date=March 23, 2017|website=The Next Web|archive-date=April 3, 2021|archive-url=https://web.archive.org/web/20210403193928/https://thenextweb.com/apple/2014/09/09/everything-apple-announced-september-2014-keynote/|url-status=live}}{{Cite web|last=Savov|first=Vlad|date=September 9, 2014|title=Apple Watch announced: available for $349 early next year|url=https://www.theverge.com/2014/9/9/6125873/apple-watch-smartwatch-announced|access-date=March 23, 2017|website=The Verge|archive-date=September 9, 2014|archive-url=https://web.archive.org/web/20140909183047/http://www.theverge.com/2014/9/9/6125873/apple-watch-smartwatch-announced|url-status=live}} It was released on April 24, 2015.{{Cite web|last=Machkovech|first=Sam|date=March 9, 2015|title=Apple Watch starts at $349, launching April 24|url=https://arstechnica.com/apple/2015/03/apple-watch-launching-on-april-24-starting-at-349/|access-date=March 23, 2017|website=Ars Technica|archive-date=March 24, 2017|archive-url=https://web.archive.org/web/20170324090414/https://arstechnica.com/apple/2015/03/apple-watch-launching-on-april-24-starting-at-349/|url-status=live}}{{Cite web|last1=Gibbs|first1=Samuel|last2=Hern|first2=Alex|date=March 9, 2015|title=Apple Watch: available 24 April for between $349 and $17,000|url=https://www.theguardian.com/technology/2015/mar/09/apple-watch-available-april-24-for-between-349-and-10000|access-date=March 23, 2017|website=The Guardian|archive-date=April 16, 2017|archive-url=https://web.archive.org/web/20170416162230/https://www.theguardian.com/technology/2015/mar/09/apple-watch-available-april-24-for-between-349-and-10000|url-status=live}}{{Cite web|last=Kastrenakes|first=Jacob|date=March 9, 2015|title=Apple Watch release date is April 24th, with pricing from $349 to over $10,000|url=https://www.theverge.com/2015/3/9/8162455/apple-watch-price-release-date-2015|access-date=March 23, 2017|website=The Verge|archive-date=October 11, 2017|archive-url=https://web.archive.org/web/20171011181924/https://www.theverge.com/2015/3/9/8162455/apple-watch-price-release-date-2015|url-status=live}} It uses watchOS as its operating system; watchOS is based on iOS, with new features created specially for the Apple Watch such as an activity tracking app.{{cite news |last1=Hamburger |first1=Ellis |title=Activity and Workout apps for Apple Watch track your moves 24/7 |url=https://www.theverge.com/2014/9/9/6127523/fitness-and-workout-apps-apple-watch |access-date=13 April 2023 |work=The Verge |date=9 September 2014 |archive-date=April 13, 2023 |archive-url=https://web.archive.org/web/20230413085020/https://www.theverge.com/2014/9/9/6127523/fitness-and-workout-apps-apple-watch |url-status=live }}

In October 2016, Apple opened its first iOS Developer Academy in Naples inside University of Naples Federico II's new campus.{{cite web|author=Juli Clover|date=October 5, 2016|title=Apple's First iOS Developer Academy Opens October 6 at University of Naples|url=http://www.macrumors.com/2016/10/05/apple-developer-academy-university-of-naples/|url-status=live|archive-url=https://web.archive.org/web/20161223132037/http://www.macrumors.com/2016/10/05/apple-developer-academy-university-of-naples/|archive-date=December 23, 2016|access-date=December 22, 2016|publisher=MacRumors}}{{cite web|author=Mike Wuerthele|date=October 5, 2016|title=Apple's first European iOS Developer Academy opening on Thursday in Naples, Italy|url=http://appleinsider.com/articles/16/10/05/apples-first-european-ios-developer-academy-opening-on-thursday-in-naples-italy|url-status=live|archive-url=https://web.archive.org/web/20161221205057/http://appleinsider.com/articles/16/10/05/apples-first-european-ios-developer-academy-opening-on-thursday-in-naples-italy|archive-date=December 21, 2016|access-date=December 22, 2016|publisher=AppleInsider}} The course is completely free, aimed at acquiring specific technical skills on the creation and management of applications for the Apple ecosystem platforms.{{Cite magazine|date=October 7, 2016|title=Chi è entrato, chi è scappato e cosa c'è dentro alla iOS Developer Academy di Napoli|url=https://www.wired.it/mobile/app/2016/10/07/dentro-alla-ios-developer-academy-di-napoli/|access-date=August 12, 2020|magazine=Wired|language=it|archive-date=November 8, 2019|archive-url=https://web.archive.org/web/20191108090453/https://www.wired.it/mobile/app/2016/10/07/dentro-alla-ios-developer-academy-di-napoli/|url-status=live}} At the academy there are also issues of business administration (business planning and business management with a focus on digital opportunities) and there is a path dedicated to the design of graphical interfaces. Students have the opportunity to participate in the "Enterprise Track", an in-depth training experience on the entire life cycle of an app, from design to implementation, to security, troubleshooting, data storage and cloud usage.{{Cite web|title=Dopo Apple in arrivo a Napoli altri big dell'hi-tech|url=https://www.ilsole24ore.com/art/dopo-apple-arrivo-napoli-altri-big-dell-hi-tech-ACXIJns|access-date=August 12, 2020|website=Il Sole 24 ORE|date=October 18, 2019|language=it|archive-date=August 15, 2020|archive-url=https://web.archive.org/web/20200815123931/https://www.ilsole24ore.com/art/dopo-apple-arrivo-napoli-altri-big-dell-hi-tech-ACXIJns|url-status=live}}{{Cite web|title=iOS Developer Academy aprirà a Napoli {{!}} In Ateneo|url=https://www.unina.it/-/12744301-ios-developer-academy-aprira-a-napoli|access-date=August 12, 2020|website=University of Naples Federico II|archive-date=April 21, 2021|archive-url=https://web.archive.org/web/20210421023213/http://www.unina.it/-/12744301-ios-developer-academy-aprira-a-napoli|url-status=live}} As of 2020, the academy graduated almost a thousand students from all over the world, who have worked on 400 app ideas and have already published about 50 apps on the iOS App Store. In the 2018–2019 academic year, students from more than 30 countries arrived. 35 of these have been selected to attend the Worldwide Developer Conference, the annual Apple Developer Conference held annually in California in early June.{{Cite web|title=Developer Academy {{!}} Università Federico II|url=https://www.unina.it/ateneo/developer-academy|access-date=August 12, 2020|website=University of Naples Federico II|archive-date=August 10, 2020|archive-url=https://web.archive.org/web/20200810122720/http://www.unina.it/ateneo/developer-academy|url-status=live}}{{Cite web|date=May 15, 2019|title=Apple Developer Academy di Napoli, al via le nuove iscrizioni|url=https://www.lastampa.it/tecnologia/news/2019/05/15/news/apple-developer-academy-di-napoli-al-via-le-nuove-iscrizioni-1.33702119|access-date=August 12, 2020|website=lastampa.it|language=it-IT|archive-date=December 19, 2019|archive-url=https://web.archive.org/web/20191219031831/https://www.lastampa.it/tecnologia/news/2019/05/15/news/apple-developer-academy-di-napoli-al-via-le-nuove-iscrizioni-1.33702119|url-status=dead}}

File:Steve Jobs with the Apple iPad no logo (cropped).jpg introduces the iPad (2010).]]

On June 3, 2019, iPadOS, the branded version of iOS for iPad, was announced at the 2019 WWDC; it was launched on September 25, 2019.{{Cite web|title=Apple unveils iPadOS, adding features specifically to iPad|url=https://appleinsider.com/articles/19/06/03/apple-supplements-ios-13-with-new-tablet-specific-ipad-os-branch|access-date=August 11, 2020|website=AppleInsider|date=June 3, 2019 |archive-date=July 13, 2019|archive-url=https://web.archive.org/web/20190713124824/https://appleinsider.com/articles/19/06/03/apple-supplements-ios-13-with-new-tablet-specific-ipad-os-branch|url-status=live}}

The iOS user interface is based upon direct manipulation, using multi-touch gestures such as swipe, tap, pinch, and reverse pinch. Interface control elements include sliders, switches, and buttons.{{Cite web|title=Interface Essentials – iOS – Human Interface Guidelines |url=https://developer.apple.com/design/human-interface-guidelines/ios/overview/interface-essentials/|access-date=August 11, 2020|website=Apple Developer|archive-date=February 10, 2022|archive-url=https://web.archive.org/web/20220210042116/https://developer.apple.com/design/human-interface-guidelines/ios/overview/interface-essentials/|url-status=live}} Internal accelerometers are used by some applications to respond to shaking the device (one common result is the undo command) or rotating it in three dimensions (one common result is switching between portrait and landscape mode). Various accessibility described in {{section link||Accessibility}} functions enable users with vision and hearing disabilities to properly use iOS.{{Cite web|title=Adaptivity and Layout – Visual Design – iOS – Human Interface Guidelines |url=https://developer.apple.com/design/human-interface-guidelines/ios/visual-design/adaptivity-and-layout/|access-date=August 11, 2020|website=Apple Developer|archive-date=February 10, 2022|archive-url=https://web.archive.org/web/20220210042116/https://developer.apple.com/design/human-interface-guidelines/ios/visual-design/adaptivity-and-layout/|url-status=live}}

iOS devices boot to the lock screen. The lock screen shows the time and a user's lock screen widgets, which display timely information from apps.{{Cite web |date=2023-02-23 |title=How to add and edit widgets on your iPhone |url=https://support.apple.com/en-us/HT207122 |access-date=2023-10-17 |website=Apple Support |language=en |archive-date=October 17, 2023 |archive-url=https://web.archive.org/web/20231017071708/https://support.apple.com/en-us/HT207122 |url-status=live }} Upon unlock, a user is directed to the home screen, which is the primary navigation and information "hub" on iOS devices, analogous to the desktop found on personal computers. iOS home screens are typically made up of app icons and widgets; app icons launch the associated app, whereas widgets display live, auto-updating content, such as a weather forecast, the user's email inbox, or a news ticker directly on the home screen.{{Cite web|title=Widgets – System Capabilities – iOS – Human Interface Guidelines – Apple Developer|url=https://developer.apple.com/design/human-interface-guidelines/ios/system-capabilities/widgets|access-date=August 11, 2020|website=Apple Developer|archive-date=August 9, 2020|archive-url=https://web.archive.org/web/20200809063632/https://developer.apple.com/design/human-interface-guidelines/ios/system-capabilities/widgets|url-status=live}}

Along the top of the screen is a status bar, showing information about the device and its connectivity. The Control Center can be "pulled" down from the top right of the notch or Dynamic Island (on iPhones with Face ID) or can be "pulled" up from the bottom to top of the screen (on iPhones with Touch ID), giving access to various toggles to manage the device more quickly without having to open the Settings. It is possible to manage brightness, volume, wireless connections, music player, etc.{{Cite web|title=Access and customize Control Center on your iPhone and iPod Touch|url=https://support.apple.com/en-us/HT202769|access-date=August 11, 2020|website=Apple Support|archive-date=October 2, 2017|archive-url=https://web.archive.org/web/20171002011705/https://support.apple.com/en-us/HT202769|url-status=live}}

Scrolling from the top left to the bottom (or top to bottom on iPhones with Touch ID) will open the Notification Center, which in the latest versions of iOS is very similar to the lock screen. It displays notifications in chronological order and groups them by application. From the notifications of some apps it is possible to interact directly, for example by replying to a message directly from it. Notifications are sent in two modes, critical alerts that are displayed on the lock screen and signaled by a distinctive sound and vibration (e.g. emergency alerts or severe weather alerts), accompanied by a warning banner and the app badge icon, and standard alerts which use a default sound and vibration. Both can be found in the Notification Center, and show for a set amount of time on the lock screen (unless the user has Notification Center allowed when locked).{{Cite web|title=Use notifications on your iPhone, iPad, and iPod Touch|url=https://support.apple.com/en-us/HT201925|access-date=August 11, 2020|website=Apple Support|archive-date=August 19, 2014|archive-url=https://web.archive.org/web/20140819154745/http://support.apple.com/kb/HT3576|url-status=live}}{{Cite web|url=https://www.imore.com/how-use-notification-center-iphone-and-ipad|title=How to find your notifications and respond when you're ready|date=December 2, 2018|website=iMore|access-date=March 3, 2021|archive-date=January 22, 2021|archive-url=https://web.archive.org/web/20210122094407/https://www.imore.com/how-use-notification-center-iphone-and-ipad|url-status=live}}

On iPhones with Touch ID, screenshots can be created with the simultaneous press of the home and power buttons. In comparison to Android, which requires the buttons to be held down, a short press does suffice on iOS.{{cite web |last1=Alex |first1=Anson |title=How to Take a Screenshot on the iPhone 5 and iOS 6 [Video] |url=https://ansonalex.com/tutorials/how-to-take-a-screenshot-on-the-iphone-5-and-ios-6/ |website=AnsonAlex.com |date=4 October 2012 |access-date=December 31, 2020 |archive-date=December 4, 2020 |archive-url=https://web.archive.org/web/20201204003206/https://ansonalex.com/tutorials/how-to-take-a-screenshot-on-the-iphone-5-and-ios-6/ |url-status=live }} On iPhone with Face ID, screenshots are captured using the volume-up and power buttons instead.{{cite web |title=How to Take a Screenshot on an iPhone X and Newer Models |url=https://www.digitaltrends.com/mobile/how-to-take-a-screenshot-on-an-iphone-x/ |website=Digital Trends |language=en |date=1 December 2020 |access-date=December 31, 2020 |archive-date=December 4, 2020 |archive-url=https://web.archive.org/web/20201204003933/https://www.digitaltrends.com/mobile/how-to-take-a-screenshot-on-an-iphone-x/ |url-status=live }}

The camera application used a skeuomorphic closing camera shutter animation prior to iOS 7. Since then, it uses a simple short blackout effect.{{cite web |title=How Functional Animation Helps Improve User Experience |url=https://www.smashingmagazine.com/2017/01/how-functional-animation-helps-improve-user-experience/ |website=Smashing Magazine |access-date=19 August 2021 |language=en |date=11 January 2017 |quote=[Image: shutter-animation-in-apple-ios-6-camera-app.png] Shutter image in the iOS 6 camera app |archive-date=August 19, 2021 |archive-url=https://web.archive.org/web/20210819215153/https://www.smashingmagazine.com/2017/01/how-functional-animation-helps-improve-user-experience/ |url-status=live }} Notable additions over time include HDR photography and the option to save both normal and high dynamic range photographs simultaneously where the former prevents ghosting effects from moving objects (since iPhone 5 on iOS 6), automatic HDR adjustment (since iOS 7.1), "live photo" with short video bundled to each photo if enabled (iPhone 6s, iOS 9), and a digital zoom shortcut (iPhone 7 Plus, iOS 10).{{cite web |title=Apple iPhone 5 Camera Review |url=https://www.dpreview.com/reviews/apple-iphone-5-review/2 |website=DPReview |access-date=19 August 2021 |date=2012-10-09 |archive-date=August 19, 2021 |archive-url=https://web.archive.org/web/20210819220754/https://www.dpreview.com/reviews/apple-iphone-5-review/2 |url-status=live }}{{cite web |last1=Cipriani |first1=Jason |title=How to enable auto-HDR in iOS 7.1 |url=https://www.cnet.com/tech/services-and-software/how-to-enable-auto-hdr-in-ios-7-1/ |website=CNET |access-date=19 August 2021 |language=en |date=2014-03-10 |archive-date=August 19, 2021 |archive-url=https://web.archive.org/web/20210819220753/https://www.cnet.com/tech/services-and-software/how-to-enable-auto-hdr-in-ios-7-1/ |url-status=live }}{{cite web |title=Camera tests: Zoom on the iPhone 7 vs iPhone 7 Plus |url=https://www.imore.com/camera-tests-zoom-iphone-7-vs-iphone-7-plus |website=iMore |access-date=19 August 2021 |date=21 September 2016 |archive-date=May 6, 2021 |archive-url=https://web.archive.org/web/20210506230737/https://www.imore.com/camera-tests-zoom-iphone-7-vs-iphone-7-plus |url-status=live }} Some camera settings such as video resolution and frame rate are not adjustable through the camera interface itself, but are outsourced to the system settings.{{cite web |title=Record HD or 4K video with your iPhone or iPad |url=https://support.apple.com/en-us/HT209431 |website=Apple Support |date=December 14, 2020 |language=en |access-date=August 19, 2021 |archive-date=August 19, 2021 |archive-url=https://web.archive.org/web/20210819220754/https://support.apple.com/en-us/HT209431 |url-status=live }}

A new feature in iOS 13 called "context menus" shows related actions when you touch and hold an item. When the context menu is displayed, the background is blurred.{{Cite web|title=Context Menus – Controls – iOS – Human Interface Guidelines – Apple Developer|url=https://developer.apple.com/design/human-interface-guidelines/ios/controls/context-menus/|access-date=August 11, 2020|website=Apple Developer|archive-date=August 3, 2020|archive-url=https://web.archive.org/web/20200803085459/https://developer.apple.com/design/human-interface-guidelines/ios/controls/context-menus/|url-status=live}}

To choose from a few options, a selection control is used. Selectors can appear anchored at the bottom or in line with the content (called date selectors). Date selectors take on the appearance of any other selection control, but with a column for day, month, and optionally year.

Alerts appear in the center of the screen, but there are also alerts that scroll up from the bottom of the screen (called "action panels"). Destructive actions (such as eliminating any element) are colored red.

The official font of iOS is San Francisco. It is designed for small text readability, and is used throughout the operating system, including third-party apps.

The icons are 180x180px in size for iPhones with a larger screen, usually models over 6 inches, including iPhone 11 Pro and iPhone 8 Plus, while they are 120x120px on iPhones with smaller displays.{{Cite web|title=Technical Q&A QA1686: App Icons on iPhone, iPad and Apple Watch|url=https://developer.apple.com/library/archive/qa/qa1686/_index.html|access-date=August 11, 2020|website=Apple Developer|archive-date=July 30, 2020|archive-url=https://web.archive.org/web/20200730234505/https://developer.apple.com/library/archive/qa/qa1686/_index.html|url-status=live}}

{{Main|SpringBoard}}

The home screen, rendered by SpringBoard, displays application icons and a dock at the bottom where users can pin their most frequently used apps. iOS home screens are typically made up of app icons and widgets; app icons launch the associated app, whereas widgets display live, auto-updating content, such as a weather forecast, the user's email inbox, or a news ticker directly on the home screen.{{Cite web |title=Add, edit, and remove widgets on iPhone |url=https://support.apple.com/guide/iphone/add-edit-and-remove-widgets-iphb8f1bf206/ios |access-date=2023-12-16 |website=Apple Support |language=en |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216134006/https://support.apple.com/guide/iphone/add-edit-and-remove-widgets-iphb8f1bf206/ios |url-status=live }} The home screen appears whenever the user unlocks the device, presses the physical "Home" button while in an app, or swipes up from the bottom of the screen using the home bar.{{cite web|title = Home button – Apple|url = http://help.apple.com/iphone/8/#/iph3bd00bbb|website = help.apple.com|access-date = May 24, 2015|archive-date = November 18, 2018|archive-url = https://web.archive.org/web/20181118200222/https://help.apple.com/iphone/8/#/iph3bd00bbb|url-status = live}} The screen has a status bar across the top to display data, such as time, battery level, and signal strength. The rest of the screen is devoted to the current application. When a passcode is set and a user switches on the device, the passcode must be entered at the Lock Screen before access to the Home screen is granted.{{cite web|title = About iOS passcodes – Apple Support|url = https://support.apple.com/en-us/HT204060|website = support.apple.com|access-date = May 24, 2015|url-status=live|archive-url = https://web.archive.org/web/20150428092931/https://support.apple.com/en-us/HT204060|archive-date = April 28, 2015|df = mdy-all}}

In iPhone OS 3, Spotlight was introduced, allowing users to search media, apps, emails, contacts, messages, reminders, calendar events, and similar content. In iOS 7 and later, Spotlight is accessed by pulling down anywhere on the home screen (except for the top and bottom edges that open Notification Center and Control Center).{{cite web | url=http://appleinsider.com/articles/13/06/10/apples-ios-7-embeds-search-bar-into-every-app-screen | title=Apple's iOS 7 brings quick Spotlight search access to every app page | work=AppleInsider | date=June 10, 2013 | access-date=September 18, 2013 | url-status=live | archive-url=https://web.archive.org/web/20131007171934/http://appleinsider.com/articles/13/06/10/apples-ios-7-embeds-search-bar-into-every-app-screen | archive-date=October 7, 2013 | df=mdy-all }}{{cite web | url=http://www.smartipadguide.com/search-on-ipad-with-spotlight-on-ios-7 | title=Search on iPad with iOS 7 | date=October 21, 2013 | access-date=March 1, 2014 | url-status=live | archive-url=https://web.archive.org/web/20150113004543/http://www.smartipadguide.com/search-on-ipad-with-spotlight-on-ios-7 | archive-date=January 13, 2015 | df=mdy-all }} In iOS 9, there are two ways to access Spotlight. As with iOS 7 and 8, pulling down on any homescreen will show Spotlight. However, it can also be accessed as it was in iOS versions 3 through 6. This endows Spotlight with Siri suggestions, which include app suggestions, contact suggestions and news.{{cite web | url=https://www.macworld.com/article/2984323/hands-on-with-the-new-proactive-spotlight-in-ios-9.html | title=Hands-on with the new, proactive Spotlight in iOS 9 | date=September 16, 2015 | access-date=September 25, 2020 | archive-date=September 23, 2020 | archive-url=https://web.archive.org/web/20200923040843/https://www.macworld.com/article/2984323/hands-on-with-the-new-proactive-spotlight-in-ios-9.html | url-status=live }} In iOS 10, Spotlight is at the top of the now-dedicated "Today" panel.{{cite web |first=Dan |last=Seifert |title=iOS 10 will make you love your lock screen |url=https://www.theverge.com/2016/7/8/12128150/ios-10-hands-on-preview-lockscreen |website=The Verge |publisher=Vox Media |date=September 13, 2016 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170210155903/http://www.theverge.com/2016/7/8/12128150/ios-10-hands-on-preview-lockscreen |archive-date=February 10, 2017 }}

With the release of iPhone OS 3.2, users gained the ability to set a wallpaper for the Home Screen. The feature was initially only available on the iPad (1st generation) until the release of iOS 4 a few months after the release of iPhone OS 3.2, which brought the feature to all iPhone and iPod Touch models that could run the operating system, with the exception of the iPhone 3G and the iPod touch (2nd generation) due to performance issues with icon animations.{{cite web | url = https://www.macrumors.com/2010/06/22/steve-jobs-on-lack-of-custom-wallpapers-in-ios-4-for-iphone-3g/ | title = Steve Jobs on Lack of Custom Wallpapers in iOS 4 for iPhone 3G | work = MacRumors | last = Slivka | first = Eric | date = June 22, 2010 | access-date = September 19, 2024}}

iOS 7 introduced a parallax effect on the Home Screen, which shifts the device's wallpaper and icons in response to the movement of the device, creating a 3D effect and an illusion of floating icons. This effect is also visible in the tab view of Mail and Safari.{{Cite web |last=Zibreg |first=Christian |date=September 26, 2016 |orig-year=June 28, 2013 |title=A closer look at iOS 7 parallax effect |url=https://www.idownloadblog.com/2013/06/28/ios-7-parallax-effect-explained/ |publisher=iDownloadBlog.com |access-date=May 5, 2022 |archive-date=May 19, 2022 |archive-url=https://web.archive.org/web/20220519000418/https://www.idownloadblog.com/2013/06/28/ios-7-parallax-effect-explained/ |url-status=live }}

Researchers found that users organize icons on their homescreens based on usage frequency and relatedness of the applications, as well as for reasons of usability and aesthetics.Matthias Böhmer, Antonio Krüger. [http://matthiasboehmer.de/2013/01/study-on-icon-arrangement/ A Study on Icon Arrangement by Smartphone Users] {{webarchive|url=https://web.archive.org/web/20130512183243/http://matthiasboehmer.de/2013/01/study-on-icon-arrangement/ |date=May 12, 2013 }}. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI '13). ACM, New York, NY, US, 2137–2146.

iOS originally used Helvetica as the system font. Apple switched to Helvetica Neue exclusively for the iPhone 4 and its Retina Display, and retained Helvetica as the system font for older iPhone devices on iOS 4.{{cite web |first=John |last=Gruber |title=4 |url=https://daringfireball.net/2010/06/4 |website=Daring Fireball |date=June 29, 2010 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171009111438/https://daringfireball.net/2010/06/4 |archive-date=October 9, 2017 }} With iOS 7, Apple announced that they would change the system font to Helvetica Neue Light, a decision that sparked criticism for inappropriate usage of a light, thin typeface for low-resolution mobile screens. Apple eventually chose Helvetica Neue instead.{{cite journal |first=Elizabeth |last=Stinson |title=Why Apple abandoned the world's most beloved typeface |url=https://www.wired.com/2015/06/apple-abandoned-worlds-beloved-typeface/ |journal=Wired |date=June 9, 2015 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20150613012051/http://www.wired.com/2015/06/apple-abandoned-worlds-beloved-typeface/ |archive-date=June 13, 2015 }}{{cite web |first=John |last=Koetsier |title=Apple 'fontgate' ends with thicker Helvetica Neue in iOS 7 beta 3 |url=https://venturebeat.com/2013/07/09/apple-fontgate-ends-with-thicker-helvetica-neue-in-ios-7-beta-3/ |website=VentureBeat |date=July 9, 2013 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171015203655/https://venturebeat.com/2013/07/09/apple-fontgate-ends-with-thicker-helvetica-neue-in-ios-7-beta-3/ |archive-date=October 15, 2017 }} The release of iOS 7 also introduced the ability to scale text or apply other forms of text accessibility changes through Settings.{{cite web |first=Sarah |last=Guarino |title=iOS 7 How-to: Make text more readable/larger on your iPad and iPhone |url=https://9to5mac.com/2013/09/21/ios-7-how-to-make-text-more-readablelarger-on-your-ipad-and-iphone/ |website=9to5Mac |date=September 21, 2013 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160731183723/http://9to5mac.com/2013/09/21/ios-7-how-to-make-text-more-readablelarger-on-your-ipad-and-iphone/ |archive-date=July 31, 2016 }}{{cite web |first=Allyson |last=Kazmucha |title=How to increase or decrease font sizes on iPhone and iPad in iOS 7 with Dynamic Type |url=https://www.imore.com/how-increase-or-decrease-font-sizes-iphone-and-ipad-ios-7-dynamic-type |website=iMore |date=November 20, 2013 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170508115332/http://www.imore.com/how-increase-or-decrease-font-sizes-iphone-and-ipad-ios-7-dynamic-type |archive-date=May 8, 2017 }} With iOS 9, Apple changed the font to San Francisco, an Apple-designed font aimed at maximum legibility and font consistency across its product lineup.{{cite web |first=Adario |last=Strange |title=All hail Apple's new iOS 9 font, San Francisco |url=http://mashable.com/2015/09/16/apple-ios-9-font/ |website=Mashable |date=September 17, 2015 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171221035219/http://mashable.com/2015/09/16/apple-ios-9-font/ |archive-date=December 21, 2017 }}{{cite web |title=Apple drops Helvetica for San Francisco in iOS 9 |url=http://appleinsider.com/articles/15/09/16/first-look-apple-drops-helvetica-for-san-francisco-in-ios-9 |website=AppleInsider |date=September 16, 2015 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170306092414/http://appleinsider.com/articles/15/09/16/first-look-apple-drops-helvetica-for-san-francisco-in-ios-9 |archive-date=March 6, 2017 }}

iOS 4 introduced folders, which can be created by dragging an application on top of another, and from then on, more items can be added to the folder using the same procedure. A title for the folder is automatically selected by the category of applications inside, but the name can also be edited by the user.{{cite web |first=Dan |last=Frakes |title=Hands on with iOS 4 folders |url=https://www.macworld.com/article/1152168/ios4folders.html |website=Macworld |publisher=International Data Group |date=June 21, 2010 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171101033003/https://www.macworld.com/article/1152168/ios4folders.html |archive-date=November 1, 2017 }} When apps inside folders receive notification badges, the individual numbers of notifications are added up and the total number is displayed as a notification badge on the folder itself. Originally, folders on an iPhone could include up to 12 apps, while folders on iPad could include 20.{{cite web |first=Lex |last=Friedman |title=How to create and organize iOS folders |url=https://www.macworld.com/article/1160291/tablets/create-organize-ios-folders.html |website=Macworld |publisher=International Data Group |date=June 20, 2011 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171015202624/https://www.macworld.com/article/1160291/tablets/create-organize-ios-folders.html |archive-date=October 15, 2017 }} With increasing display sizes on newer iPhone hardware, iOS 7 updated the folders with pages similar to the home screen layout, allowing for a significant expansion of folder functionality. Each page of a folder can contain up to nine apps, and there can be 15 pages in total, allowing for a total of 135 apps in a single folder.{{cite web |first=Sam |last=Costello |title=How Many Apps and Folders Can an iPhone Have? |url=https://www.lifewire.com/how-many-apps-allowed-iphone-2000752 |website=Lifewire |publisher=Dotdash |date=March 20, 2017 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170806182301/https://www.lifewire.com/how-many-apps-allowed-iphone-2000752 |archive-date=August 6, 2017 }} In iOS 9, Apple updated folder sizes for iPad hardware, allowing for 16 apps per page, still at 15 pages maximum, increasing the total to 240 apps.{{cite web |first=Chance |last=Miller |title=iOS 9 lets you store 105 more apps per folder on the iPad |url=https://9to5mac.com/2015/07/08/new-folders-ios-9/ |website=9to5Mac |date=July 8, 2015 |access-date=October 15, 2017 |url-status=live |archive-url=https://web.archive.org/web/20171015150809/https://9to5mac.com/2015/07/08/new-folders-ios-9/ |archive-date=October 15, 2017 }}

{{Main|Notification Center}}

Before iOS 5, notifications were delivered in a modal window and could not be viewed after being dismissed. In iOS 5, Apple introduced Notification Center, which allows users to view a history of notifications. The user can tap a notification to open its corresponding app, or clear it.{{cite web|url=https://www.apple.com/au/iphone/features/notification-center.html |title=iPhone 4S – Always know what's up in Notification Center |publisher=Apple Inc. |archive-url=https://web.archive.org/web/20120214123941/http://www.apple.com/au/iphone/features/notification-center.html |archive-date=February 14, 2012 |url-status=dead }} Notifications are now delivered in banners that appear briefly at the top of the screen. If a user taps a received notification, the application that sent the notification will be opened. Users can also choose to view notifications in modal alert windows by adjusting the application's notification settings. Introduced with iOS 8, widgets are now accessible through the Notification Center, defined by 3rd parties.{{Cite web |title=How to use widgets on iOS 8 |url=https://www.cnet.com/tech/mobile/how-to-use-widgets-on-ios-8/ |access-date=2023-12-16 |website=CNET |language=en}}

When an app sends a notification while closed, a red badge appears on its icon. This badge tells the user, at a glance, how many notifications that app has sent. Opening the app clears the badge.

{{See also|List of built-in iOS apps|App Store (Apple)|.ipa}}

iOS devices come with preinstalled apps developed by Apple including Mail, Maps, TV, Music, FaceTime, Wallet, Health, and many more.

Applications ("apps") are the most general form of application software that can be installed on iOS. They are downloaded from the official catalog of the App Store digital store, where apps are subjected to security checks before being made available to users. In June 2017, Apple updated its guidelines to specify that app developers will no longer have the ability to use custom prompts for encouraging users to leave reviews for their apps.{{cite web |last=Kastrenakes |first=Jacob |date=June 9, 2017 |title=Apple won't let apps annoy you with their own review prompts anymore |url=https://www.theverge.com/2017/6/9/15768196/apple-ending-annoying-app-store-review-prompts |url-status=live |archive-url=https://web.archive.org/web/20170609200122/https://www.theverge.com/2017/6/9/15768196/apple-ending-annoying-app-store-review-prompts |archive-date=June 9, 2017 |access-date=June 14, 2017 |website=The Verge |publisher=Vox Media}}{{cite web |last=Mayo |first=Benjamin |date=June 9, 2017 |title=App Store now requires developers to use official API to request app ratings, disallows custom prompts |url=https://9to5mac.com/2017/06/09/app-rating-custom-prompts-app-store-banned/ |url-status=live |archive-url=https://web.archive.org/web/20170612140318/https://9to5mac.com/2017/06/09/app-rating-custom-prompts-app-store-banned/ |archive-date=June 12, 2017 |access-date=June 14, 2017 |website=9to5Mac}} IOS applications can also be installed directly from an IPA file provided by the software distributor, via unofficial ways. They are written using iOS Software Development Kit (SDK) and, often, combined with Xcode, using officially supported programming languages, including Swift and Objective-C. Other companies have also created tools that allow for the development of native iOS apps using their respective programming languages.

Applications for iOS are mostly built using components of UIKit, a programming framework. It allows applications to have a consistent look and feel with the OS, nevertheless offering customization.

Elements automatically update along with iOS updates, automatically including new interface rules. UIKit elements are very adaptable, this allows developers to design a single app that looks the same on any iOS device. In addition to defining the iOS interface, UIKit defines the functionality of the application.

At first, Apple did not intend to release an SDK to developers, because they did not want third-party apps to be developed for iOS, building web apps instead. However, this technology never entered into common use, this led Apple to change its opinion, so in October 2007 the SDK for developers was announced, finally released on March 6, 2008.

The SDK includes an inclusive set of development tools,{{cite web |last=Kim |first=Arnold |date=March 6, 2008 |title=Apple Releases iPhone SDK, Demos Spore, Instant Messaging |url=https://www.macrumors.com/2008/03/06/apple-releases-iphone-sdk-demos-spore-instant-messaging/ |url-status=live |archive-url=https://web.archive.org/web/20160311195044/http://www.macrumors.com/2008/03/06/apple-releases-iphone-sdk-demos-spore-instant-messaging/ |archive-date=March 11, 2016 |access-date=June 11, 2017 |website=MacRumors}} including an audio mixer and an iPhone simulator. It is a free download for Mac users. It is not available for Microsoft Windows PCs. To test the application, get technical support, and distribute applications through App Store, developers are required to subscribe to the Apple Developer Program.

Over the years, the Apple Store apps surpassed multiple major milestones, including 50,000,{{cite web |last=Siegler |first=MG |date=June 8, 2009 |title=State Of The iPhone Ecosystem: 40 Million Devices and 50,000 Apps |url=https://techcrunch.com/2009/06/08/40-million-iphones-and-ipod-touches-and-50000-apps/ |url-status=live |archive-url=https://web.archive.org/web/20090610235745/http://www.techcrunch.com/2009/06/08/40-million-iphones-and-ipod-touches-and-50000-apps/ |archive-date=June 10, 2009 |access-date=March 29, 2017 |website=TechCrunch |publisher=AOL}} 100,000,{{cite web |date=November 4, 2009 |title=Apple Announces Over 100,000 Apps Available on the App Store |url=https://www.macrumors.com/2009/11/04/apple-announces-over-100000-apps-available-on-the-app-store/ |url-status=live |archive-url=https://web.archive.org/web/20190330120948/https://www.macrumors.com/2009/11/04/apple-announces-over-100000-apps-available-on-the-app-store/ |archive-date=March 30, 2019 |access-date=March 29, 2017 |website=MacRumors}} 250,000,{{cite web |last=Brian |first=Matt |date=August 28, 2010 |title=Apple's App Store Now Features 250,000 Apps |url=https://thenextweb.com/mobile/2010/08/28/apples-app-store-now-features-250000-apps/ |url-status=live |archive-url=https://web.archive.org/web/20170329233606/https://thenextweb.com/mobile/2010/08/28/apples-app-store-now-features-250000-apps/ |archive-date=March 29, 2017 |access-date=March 29, 2017 |website=The Next Web}} 500,000,{{cite web |last=Grothaus |first=Michael |date=October 4, 2011 |title=More than 18 billion apps downloaded from App Store |url=https://www.engadget.com/2011/10/04/more-than-18-billion-apps-downloaded-from-app-store/ |url-status=live |archive-url=https://web.archive.org/web/20170421125437/https://www.engadget.com/2011/10/04/more-than-18-billion-apps-downloaded-from-app-store/ |archive-date=April 21, 2017 |access-date=March 31, 2017 |website=Engadget |publisher=AOL}} 1 million,{{cite web |last=Ingraham |first=Nathan |date=October 22, 2013 |title=Apple announces 1 million apps in the App Store, more than 1 billion songs played on iTunes radio |url=https://www.theverge.com/2013/10/22/4866302/apple-announces-1-million-apps-in-the-app-store |url-status=live |archive-url=https://web.archive.org/web/20170512171633/https://www.theverge.com/2013/10/22/4866302/apple-announces-1-million-apps-in-the-app-store |archive-date=May 12, 2017 |access-date=March 31, 2017 |website=The Verge |publisher=Vox Media}} and 2 million apps.{{cite web |last=Golson |first=Jordan |date=June 13, 2016 |title=Apple's App Store now has over 2 million apps |url=https://www.theverge.com/2016/6/13/11922926/apple-apps-2-million-wwdc-2016 |url-status=live |archive-url=https://web.archive.org/web/20170210135527/http://www.theverge.com/2016/6/13/11922926/apple-apps-2-million-wwdc-2016 |archive-date=February 10, 2017 |access-date=March 31, 2017 |website=The Verge |publisher=Vox Media}} The billionth application was installed on April 24, 2009.{{cite web |date=April 24, 2009 |title=Apple's Revolutionary App Store Downloads Top One Billion in Just Nine Months |url=https://www.apple.com/pr/library/2009/04/24Apples-Revolutionary-App-Store-Downloads-Top-One-Billion-in-Just-Nine-Months.html |url-status=live |archive-url=https://web.archive.org/web/20170315100024/http://www.apple.com/pr/library/2009/04/24Apples-Revolutionary-App-Store-Downloads-Top-One-Billion-in-Just-Nine-Months.html |archive-date=March 15, 2017 |access-date=March 29, 2017 |website=Apple Press Info |publisher=Apple Inc.}}

App Library automatically categorizes apps into folders based on their function or type and includes an alphabetical list of all installed apps. For example, it might group all social media apps into one folder and productivity apps into another.{{Cite web |title=How to Use the App Library to Organize Your iPhone or iPad Home Screen |url=https://www.pcmag.com/how-to/how-to-organize-your-home-screen-with-ios-14s-app-library |access-date=2023-12-16 |website=PCMAG |language=en}} Users can quickly find and access apps by using the search bar at the top of the App Library. Users can choose to hide specific app pages from the home screen, making it easier to focus on the apps they use most frequently.{{Cite web |date=2023-11-16 |title=Organize the Home Screen and App Library on your iPhone |url=https://support.apple.com/en-us/HT211345 |access-date=2023-12-16 |website=Apple Support |language=en |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216134005/https://support.apple.com/en-us/HT211345 |url-status=live }}

{{See also|iCloud}}

iOS enforces strict sandboxing to maintain security and privacy. Apps are generally limited to accessing their own containers and specific system-provided directories, such as the Photos library. To access files outside of their sandbox, iOS uses mechanisms like document pickers, file providers, and app extensions.

iOS 8 introduced the Document Picker and Document Provider extensions as part of the document interaction controller.{{Cite web |title=App Extension Programming Guide: Document Provider |url=https://developer.apple.com/library/archive/documentation/General/Conceptual/ExtensibilityPG/FileProvider.html |access-date=2023-12-16 |website=Apple Developer |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216142528/https://developer.apple.com/library/archive/documentation/General/Conceptual/ExtensibilityPG/FileProvider.html |url-status=live }}{{Cite web |title=UIDocumentPickerExtensionViewController |url=https://docs.developer.apple.com/documentation/uikit/uidocumentpickerextensionviewcontroller |access-date=2023-12-16 |website=Apple Developer Documentation |language=en-US}}{{Cite web |last=updated |first=Rene Ritchie last |date=2014-07-22 |title=Document provider extensions in iOS 8: Explained |url=https://www.imore.com/ios-8-document-provider-extensions-explained |access-date=2023-12-16 |website=iMore |language=en |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216142528/https://www.imore.com/ios-8-document-provider-extensions-explained |url-status=live }} This allows apps to open, save, and interact with documents stored in a central location or cloud storage services.

With iOS 11, Apple introduced the Files app{{Cite web |title=How to Use the New Files App in iOS 11 |url=https://www.macrumors.com/how-to/files-app-ios-11/ |access-date=2023-12-16 |website=macrumors.com |date=September 19, 2017 |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216142528/https://www.macrumors.com/how-to/files-app-ios-11/ |url-status=live }} and the File Provider extension,{{Cite web |title=File Provider |url=https://docs.developer.apple.com/documentation/fileprovider/ |access-date=2023-12-16 |website=Apple Developer Documentation |language=en-US}} providing a central location for users to manage and organize their files. Apps can integrate with the Files app to make their documents accessible and editable directly from the Files app.

The storage of iOS devices can be expanded through iCloud, the Apple's cloud-based storage solution that provides 5GB of storage for free to all users, while other plans require a paid subscription. iCloud Drive allows users to store various types of files, such as documents, presentations, and spreadsheets, in the cloud. These files can be accessed across multiple devices as long as the user is signed in with the same Apple ID.

iOS offers various accessibility features to help users with vision and hearing disabilities. One major feature, VoiceOver, provides a voice reading information on the screen, including contextual buttons, icons, links and other user interface elements, and allows the user to navigate the operating system through gestures. Any apps with default controls and developed with a UIKit framework gets VoiceOver functionality built in.{{cite web |first=Mike |last=Tanasychuk |title=How to use VoiceOver on iPhone and iPad |url=http://www.imore.com/how-use-voiceover-iphone-and-ipad |website=iMore |date=September 15, 2016 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20161220131037/http://www.imore.com/how-use-voiceover-iphone-and-ipad |archive-date=December 20, 2016 }} One example includes holding up the iPhone to take a photo, with VoiceOver describing the photo scenery.{{cite web |first=Shara |last=Tibken |title=Seeing eye phone: Giving independence to the blind |url=https://www.cnet.com/news/apple-iphone-voiceover-technology-for-the-blind/ |website=CNET |publisher=CBS Interactive |date=March 25, 2016 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401060628/https://www.cnet.com/news/apple-iphone-voiceover-technology-for-the-blind/ |archive-date=April 1, 2017 }} As part of a "Made for iPhone" program, introduced with the release of iOS 7 in 2013, Apple has developed technology to use Bluetooth and a special technology protocol to let compatible third-party equipment connect with iPhones and iPads for streaming audio directly to a user's ears. Additional customization available for Made for iPhone products include battery tracking and adjustable sound settings for different environments.{{cite web |first=Shara |last=Tibken |title=Apple iPhone tech helps reinvent the hearing aid |url=https://www.cnet.com/news/apple-iphone-hearing-aid-tech-deaf-ios-accessibility-cochlear-starkey-bluetooth-watch/ |website=CNET |publisher=CBS Interactive |date=November 3, 2016 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401063911/https://www.cnet.com/news/apple-iphone-hearing-aid-tech-deaf-ios-accessibility-cochlear-starkey-bluetooth-watch/ |archive-date=April 1, 2017 }}{{cite web |first=Anthony |last=Wing Kosner |title=Made For iPhone Hearing Aids: Hands On With Halo, A Mission-Critical Wearable |url=https://www.forbes.com/sites/anthonykosner/2014/08/16/made-for-iphone-hearing-aids-hands-on-with-halo-a-mission-critical-wearable/ |website=Forbes |date=August 16, 2014 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401062155/https://www.forbes.com/sites/anthonykosner/2014/08/16/made-for-iphone-hearing-aids-hands-on-with-halo-a-mission-critical-wearable/ |archive-date=April 1, 2017 }} Apple made further efforts for accessibility for the release of iOS 10 in 2016, adding a new pronunciation editor to VoiceOver, adding a Magnifier setting to enlarge objects through the device's camera, software TTY support for deaf people to make phone calls from the iPhone, and giving tutorials and guidelines for third-party developers to incorporate proper accessibility functions into their apps.{{cite web |first=Steven |last=Aquino |title=Accessibility was all around this year's WWDC |url=https://techcrunch.com/2016/06/26/accessibility-was-all-around-this-years-wwdc/ |website=TechCrunch |publisher=AOL |date=June 26, 2016 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401055914/https://techcrunch.com/2016/06/26/accessibility-was-all-around-this-years-wwdc/ |archive-date=April 1, 2017 }}

In 2012, Liat Kornowski from The Atlantic wrote that "the iPhone has turned out to be one of the most revolutionary developments since the invention of Braille",{{cite web |first=Liat |last=Kornowski |title=How the Blind Are Reinventing the iPhone |url=https://www.theatlantic.com/technology/archive/2012/05/how-the-blind-are-reinventing-the-iphone/256589/ |website=The Atlantic |publisher=Atlantic Media |date=May 2, 2012 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401055505/https://www.theatlantic.com/technology/archive/2012/05/how-the-blind-are-reinventing-the-iphone/256589/ |archive-date=April 1, 2017 }} and in 2016, Steven Aquino of TechCrunch described Apple as "leading the way in assistive technology", with Sarah Herrlinger, Senior Manager for Global Accessibility Policy and Initiatives at Apple, stating that "We see accessibility as a basic human right. Building into the core of our products supports a vision of an inclusive world where opportunity and access to information are barrier-free, empowering individuals with disabilities to achieve their goals".{{cite web |first=Steven |last=Aquino |title=When it comes to accessibility, Apple continues to lead in awareness and innovation |url=https://techcrunch.com/2016/05/19/when-it-comes-to-accessibility-apple-continues-to-lead-in-awareness-and-innovation/ |website=TechCrunch |publisher=AOL |date=May 19, 2016 |access-date=March 31, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401144536/https://techcrunch.com/2016/05/19/when-it-comes-to-accessibility-apple-continues-to-lead-in-awareness-and-innovation/ |archive-date=April 1, 2017 }}

Criticism has been aimed at iOS depending on both internet connection (either WiFi or through iTunes) and a working SIM card upon first activation.{{cite web |last1=Haslam |first1=Karen |title=How to activate an iPhone without a SIM card (or Wi-Fi) |url=https://www.macworld.co.uk/how-to/activate-iphone-without-sim-3643294/ |website=Macworld UK |access-date=December 31, 2020 |archive-date=December 13, 2020 |archive-url=https://web.archive.org/web/20201213221343/https://www.macworld.co.uk/how-to/activate-iphone-without-sim-3643294/ |url-status=live }} This restriction has been loosened in iOS 12, which no longer requires the latter.{{cite web |title=How to Activate iPhone without SIM? |url=https://www.wootechy.com/activation-bypass/how-to-activate-an-iphone-without-sim/ |website=www.wootechy.com |language=en |access-date=December 31, 2020 |archive-date=December 31, 2020 |archive-url=https://web.archive.org/web/20201231222422/https://www.wootechy.com/activation-bypass/how-to-activate-an-iphone-without-sim/ |url-status=live }}

Multitasking for iOS was first released in June 2010 along with the release of iOS 4.{{cite web|title=iOS 4 iPhone Update RELEASED: A Guide To iOS 4|url=http://www.huffingtonpost.com/2010/06/21/ios-4-iphone-update-relea_n_619343.html|work=The Huffington Post|access-date=April 13, 2013|date=June 21, 2010|url-status=live|archive-url=https://web.archive.org/web/20111229042916/http://www.huffingtonpost.com/2010/06/21/ios-4-iphone-update-relea_n_619343.html|archive-date=December 29, 2011}}{{cite web|last=Albanesius|first=Chloe|title=Apple iPhone iOS 4 Software Update Expected Monday|url=https://www.pcmag.com/article2/0,2817,2365351,00.asp|publisher=PC Magazine|access-date=April 14, 2013|date=June 21, 2010|url-status=live|archive-url=https://web.archive.org/web/20140623143241/http://www.pcmag.com/article2/0,2817,2365351,00.asp|archive-date=June 23, 2014}} Only certain devices—iPhone 4, iPhone 3GS, and iPod Touch 3rd generation—were able to multitask.{{cite web |first=Jacqui |last=Cheng |title=Ars reviews iOS 4: what's new, notable, and what needs work |url=https://arstechnica.com/apple/2010/06/ars-reviews-ios-4-whats-new-and-notable/ |website=Ars Technica |date=June 21, 2010 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081218/https://arstechnica.com/apple/2010/06/ars-reviews-ios-4-whats-new-and-notable/ |archive-date=April 2, 2017 }} The iPad did not get multitasking until iOS 4.2.1 in that November.{{cite magazine|last=Ray|first=Bill|title=iOS 4.2 multi-tasking comes to the iPad|magazine=Wired|url=https://www.wired.com/gadgetlab/2010/09/ipad-ios42/|publisher=The Register|access-date=April 14, 2013|date=November 22, 2010|url-status=live|archive-url=https://web.archive.org/web/20130613233244/http://www.wired.com/gadgetlab/2010/09/ipad-ios42|archive-date=June 13, 2013}}

The implementation of multitasking in iOS has been criticized for its approach, which limits the work that applications in the background can perform to a limited function set and requires application developers to add explicit support for it.{{cite web|last=Newman|first=Jared|title=Multitasking With iOS 4 is Horrible: Apple Blew It|url=http://www.pcworld.com/article/199528/Multitasking_With_iOS_4_is_Horrible_Apple_Blew_It.html|publisher=PC World|access-date=April 14, 2013|date=June 22, 2010|url-status=live|archive-url=https://web.archive.org/web/20130629185931/http://www.pcworld.com/article/199528/Multitasking_With_iOS_4_is_Horrible_Apple_Blew_It.html|archive-date=June 29, 2013}}

Before iOS 4, multitasking was limited to a selection of the applications Apple included on the device. Users could however "jailbreak" their device in order to unofficially multitask.{{cite web |url= https://www.imore.com/ios-4-review |title= iOS 4 review |website=iMore |first1=Rene |last1=Ritchie |date= June 14, 2010 |access-date= September 25, 2020 |archive-date= June 15, 2018 |archive-url= https://web.archive.org/web/20180615111736/https://www.imore.com/ios-4-review |url-status= live }} Starting with iOS 4, on third-generation and newer iOS devices, multitasking is supported through seven background APIs:{{cite web |url= https://www.imore.com/apple-announces-multitasking-iphone-40 |website=iMore |first1=Rene |last1=Ritchie |title= Apple announces multitasking for iPhone OS 4 (iPhone 3GS/iPod Touch G3 only) |date= April 8, 2010 |access-date= September 25, 2020 |archive-date= September 24, 2020 |archive-url= https://web.archive.org/web/20200924015005/https://www.imore.com/apple-announces-multitasking-iphone-40 |url-status= dead }}

1. Background audio – application continues to run in the background as long as it is playing audio or video content{{cite web |url=https://developer.apple.com/library/ios/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html |title=App Programming Guide for iOS – Background Execution |date=2014-09-17 |publisher=Apple Developer |access-date=September 4, 2015 |url-status=dead |archive-url=https://web.archive.org/web/20150727054318/https://developer.apple.com/library/ios/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html |archive-date=July 27, 2015 }}
2. Voice over IP – application is suspended when a phone call is not in progress
3. Background location – application is notified of location changes
4. Push notifications
5. Local notifications – application schedules local notifications to be delivered at a predetermined time
6. Task completion – application asks the system for extra time to complete a given task
7. Fast app switching – application does not execute any code and may be removed from memory at any time

In iOS 5, three new background APIs were introduced:

1. Newsstand – application can download content in the background to be ready for the user
2. External Accessory – application communicates with an external accessory and shares data at regular intervals
3. Bluetooth Accessory – application communicates with a bluetooth accessory and shares data at regular intervals

In iOS 7, Apple introduced a new multitasking feature, providing all apps with the ability to perform background updates. This feature prefers to update the user's most frequently used apps and prefers to use Wi-Fi networks over a cellular network, without markedly reducing the device's battery life.

In iOS 4.0 to iOS 6.x, double-clicking the home button activates the application switcher. A scrollable dock-style interface appears from the bottom, moving the contents of the screen up. Choosing an icon switches to an application. To the far left are icons which function as music controls, a rotation lock, and on iOS 4.2 and above, a volume controller.

With the introduction of iOS 7, double-clicking the home button also activates the application switcher. However, unlike previous versions it displays screenshots of open applications on top of the icon and horizontal scrolling allows for browsing through previous apps, and it is possible to close applications by dragging them up, similar to how WebOS handled multiple cards.{{cite web|title=Jon Rubinstein: OS X and iOS 7 borrow features from webOS|url=http://www.tuaw.com/2013/06/12/jon-rubinstein-os-x-and-ios-7-borrow-features-from-webos/ |website=TUAW |access-date=September 23, 2013|author=Yoni Heisler|date=June 12, 2013|url-status=usurped |archive-url=https://web.archive.org/web/20130928040445/http://www.tuaw.com/2013/06/12/jon-rubinstein-os-x-and-ios-7-borrow-features-from-webos/|archive-date=September 28, 2013}}

With the introduction of iOS 9, the application switcher received a significant visual change; while still retaining the card metaphor introduced in iOS 7, the application icon is smaller, and appears above the screenshot (which is now larger, due to the removal of "Recent and Favorite Contacts"), and each application "card" overlaps the other, forming a rolodex effect as the user scrolls. Now, instead of the home screen appearing at the leftmost of the application switcher, it appears rightmost.{{cite web|last1=Prabhu|first1=Gautam|title=iOS 9 vs. iOS 8: A look at the UI changes in iOS 9|url=http://www.iphonehacks.com/2015/06/ios-9-vs-ios-8-a-look-at-the-ui-changes-in-ios-9.html|website=iPhone Hacks|date=June 17, 2015|access-date=September 20, 2015|url-status=dead |archive-url=https://web.archive.org/web/20151107041632/http://www.iphonehacks.com/2015/06/ios-9-vs-ios-8-a-look-at-the-ui-changes-in-ios-9.html|archive-date=November 7, 2015}} In iOS 11, the application switcher receives a major redesign. In the iPad, the Control Center and app switcher are combined. The app switcher in the iPad can also be accessed by swiping up from the bottom. In the iPhone, the app switcher cannot be accessed if there are no apps in the RAM.

In iOS 4.0 to iOS 6.x, briefly holding the icons in the application switcher makes them "jiggle" (similarly to the homescreen) and allows the user to force quit the applications by tapping the red minus circle that appears at the corner of the app's icon.{{cite web|title=iOS: Force an app to close|url=http://support.apple.com/kb/HT5137|publisher=Apple Inc.|access-date=October 9, 2012|url-status=live|archive-url=https://web.archive.org/web/20120930234318/http://support.apple.com/kb/HT5137|archive-date=September 30, 2012}} Clearing applications from multitasking stayed the same from iOS 4.0 through 6.1.6, the last version of iOS 6.

As of iOS 7, the process has become faster and easier. In iOS 7, instead of holding the icons to close them, they are closed by simply swiping them upwards off the screen. Up to three apps can be cleared at a time compared to one in versions up to iOS 6.1.6.{{cite web|title=iOS 7 multitasking|url=http://www.tuaw.com/2013/09/18/ios-7-multitasking-has-a-brand-new-look/|publisher=Tuaw|access-date=March 21, 2014|date=September 18, 2013|url-status=live|archive-url=https://web.archive.org/web/20140221045014/http://www.tuaw.com/2013/09/18/ios-7-multitasking-has-a-brand-new-look/|archive-date=February 21, 2014}}

Task completion allows apps to continue a certain task after the app has been suspended.{{cite web|last=Snell|first=Jason|title=Inside iPhone 4.0's multitasking|url=http://www.macworld.com/article/1150496/multitasking_iphone.html|publisher=Macworld|access-date=April 14, 2013|date=April 8, 2010|url-status=live|archive-url=https://web.archive.org/web/20130530231748/http://www.macworld.com/article/1150496/multitasking_iphone.html|archive-date=May 30, 2013}}{{cite web |first=Kent |last=German |title=Apple iPhone 4 AT&T review |url=https://www.cnet.com/products/apple-iphone-4-at-t/review/ |website=CNET |publisher=CBS Interactive |date=June 23, 2010 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402080855/https://www.cnet.com/products/apple-iphone-4-at-t/review/ |archive-date=April 2, 2017 }} As of iOS 4.0, apps can request up to ten minutes to complete a task in the background.{{cite web|last=Hollington|first=Jesse|title=Instant Expert: Secrets & Features of iOS 4|url=http://www.ilounge.com/index.php/articles/comments/instant-expert-secrets-features-of-ios-4/|publisher=iLounge|access-date=April 14, 2013|date=June 21, 2010|url-status=live|archive-url=https://web.archive.org/web/20121221165136/http://www.ilounge.com/index.php/articles/comments/instant-expert-secrets-features-of-ios-4/|archive-date=December 21, 2012}} This doesn't extend to background uploads and downloads though (e.g. if a user starts a download in one application, it won't finish if they switch away from the application).

{{Main|Siri}}

Siri ({{IPAc-en|ˈ|s|ɪr|i}}) is a virtual assistant integrated into iOS. The assistant uses voice queries and a natural-language user interface to answer questions, make recommendations, and perform actions by delegating requests to a set of Internet services. The software adapts to users' individual language usages, searches, and preferences, with continuing use. Returned results are individualized.

Originally released as an app for iOS in February 2010,{{cite web |first=Erick |last=Schonfeld |title=Siri's IPhone App Puts A Personal Assistant In Your Pocket |url=https://techcrunch.com/2010/02/04/siri-iphone-personal-assistant/ |website=TechCrunch |publisher=AOL |date=February 4, 2010 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728114439/https://techcrunch.com/2010/02/04/siri-iphone-personal-assistant/ |archive-date=July 28, 2017 }} it was acquired by Apple two months later,{{cite web |first=Jenna |last=Wortham |title=Apple Buys a Start-Up for Its Voice Technology |url=https://www.nytimes.com/2010/04/29/technology/29apple.html |website=The New York Times |date=April 29, 2010 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728084120/http://www.nytimes.com/2010/04/29/technology/29apple.html |archive-date=July 28, 2017 }}{{cite web |first=Katie |last=Marsal |title=Apple acquires Siri, developer of personal assistant app for iPhone |url=http://appleinsider.com/articles/10/04/28/apple_acquires_siri_developer_of_personal_assistant_app_for_iphone |website=AppleInsider |date=April 28, 2010 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170527081510/http://appleinsider.com/articles/10/04/28/apple_acquires_siri_developer_of_personal_assistant_app_for_iphone |archive-date=May 27, 2017 }}{{cite web |first=Leena |last=Rao |title=Confirmed: Apple Buys Virtual Personal Assistant Startup Siri |url=https://techcrunch.com/2010/04/28/apple-buys-virtual-personal-assistant-startup-siri/ |website=TechCrunch |publisher=AOL |date=April 28, 2010 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170623060933/https://techcrunch.com/2010/04/28/apple-buys-virtual-personal-assistant-startup-siri/ |archive-date=June 23, 2017 }} and then integrated into iPhone 4S at its release in October 2011.{{cite web |first=Jordan |last=Golson |title=Siri Voice Recognition Arrives On the iPhone 4S |url=https://www.macrumors.com/2011/10/04/siri-voice-recognition-arrives-on-the-iphone-4s/ |website=MacRumors |date=October 4, 2011 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728082408/https://www.macrumors.com/2011/10/04/siri-voice-recognition-arrives-on-the-iphone-4s/ |archive-date=July 28, 2017 }}{{cite web |first=Chris |last=Velazco |title=Apple Reveals Siri Voice Interface: The "Intelligent Assistant" Only For iPhone 4S |url=https://techcrunch.com/2011/10/04/apple-reveals-siri-voice-interface-the-intelligent-assistant/ |website=TechCrunch |publisher=AOL |date=October 4, 2011 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728115128/https://techcrunch.com/2011/10/04/apple-reveals-siri-voice-interface-the-intelligent-assistant/ |archive-date=July 28, 2017 }} At that time, the separate app was also removed from the iOS App Store.{{cite web |first=Greg |last=Kumparak |title=The Original Siri App Gets Pulled From The App Store, Servers To Be Killed |url=https://techcrunch.com/2011/10/04/the-original-siri-app-gets-pulled-from-the-app-store-servers-killed/ |website=TechCrunch |publisher=AOL |date=October 4, 2011 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20120821141157/http://techcrunch.com/2011/10/04/the-original-siri-app-gets-pulled-from-the-app-store-servers-killed/ |archive-date=August 21, 2012 }}

Siri supports a wide range of user commands, including performing phone actions, checking basic information, scheduling events and reminders, handling device settings, searching the Internet, navigating areas, finding information on entertainment, and is able to engage with iOS-integrated apps.{{cite web |first1=Sarah Jacobsson |last1=Purewal |first2=Jason |last2=Cipriani |title=The complete list of Siri commands |url=https://www.cnet.com/how-to/the-complete-list-of-siri-commands/ |website=CNET |publisher=CBS Interactive |date=February 16, 2017 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170624114306/https://www.cnet.com/how-to/the-complete-list-of-siri-commands/ |archive-date=June 24, 2017 }} With the release of iOS 10 in 2016, Apple opened up limited third-party access to Siri, including third-party messaging apps, as well as payments, ride-sharing, and Internet calling apps.{{cite web |first=Husain |last=Sumra |title=Apple Opens Siri to Third-Party Developers With iOS 10 |url=https://www.macrumors.com/2016/06/13/apple-siri-api-third-party-developers/ |website=MacRumors |date=June 13, 2016 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728080623/https://www.macrumors.com/2016/06/13/apple-siri-api-third-party-developers/ |archive-date=July 28, 2017 }}{{cite web |first=Nathan |last=Olivarez-Giles |title=Apple iOS 10 Opens Up Siri and Messages, Updates Music, Photos and More |url=https://www.wsj.com/articles/apple-ios-10-opens-up-siri-and-messages-updates-music-photos-and-more-1465851484 |website=The Wall Street Journal |date=June 13, 2016 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728115246/https://www.wsj.com/articles/apple-ios-10-opens-up-siri-and-messages-updates-music-photos-and-more-1465851484 |archive-date=July 28, 2017 }} {{subscription required}} With the release of iOS 11, Apple updated Siri's voices for more clear, human voices, it now supports follow-up questions and language translation, and additional third-party actions.{{cite web |first=Lucas |last=Matney |title=Siri gets language translation and a more human voice |url=https://techcrunch.com/2017/06/05/siri-gets-voice-translation-and-a-more-human-voice/ |website=TechCrunch |publisher=AOL |date=June 5, 2017 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170615141047/https://techcrunch.com/2017/06/05/siri-gets-voice-translation-and-a-more-human-voice/ |archive-date=June 15, 2017 }}{{cite web |first=Chaim |last=Gartenberg |title=Siri on iOS 11 gets improved speech and can suggest actions based on how you use it |url=https://www.theverge.com/2017/6/5/15732136/apple-siri-update-announced-new-features-wwdc-2017 |website=The Verge |publisher=Vox Media |date=June 5, 2017 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170619081752/https://www.theverge.com/2017/6/5/15732136/apple-siri-update-announced-new-features-wwdc-2017 |archive-date=June 19, 2017 }} iOS 17 enabled users to activate Siri by simply saying “Siri”, while the previous command, “Hey Siri”, is still supported.

{{Main|Game Center}}

Game Center is an online multiplayer "social gaming network"{{cite web |url= https://developer.apple.com/technologies/iphone/whats-new.html#gamecenter |title= What's New in iOS 4 |publisher= Apple |access-date= June 14, 2010 |url-status=live |archive-url= https://web.archive.org/web/20100617053052/http://developer.apple.com/technologies/iphone/whats-new.html#gamecenter |archive-date= June 17, 2010 |df= mdy-all }} released by Apple.{{cite news |url=http://content.usatoday.com/communities/gamehunters/post/2010/09/apples-game-center-debuts-next-week/1 |title=Apple's Game Center debuts next week – Game Hunters: In search of video games and interactive awesomeness |work=USA Today |date=January 9, 2010 |access-date=September 1, 2010 |archive-url=https://archive.today/20120525161111/http://content.usatoday.com/communities/gamehunters/post/2010/09/apples-game-center-debuts-next-week/1 |archive-date=May 25, 2012 |url-status=live }} It allows users to "invite friends to play a game, start a multiplayer game through matchmaking, track their achievements, and compare their high scores on a leaderboard." iOS 5 and above adds support for profile photos.

Game Center was announced during an iOS 4 preview event hosted by Apple on April 8, 2010. A preview was released to registered Apple developers in August. It was released on September 8, 2010, with iOS 4.1 on iPhone 4, iPhone 3GS, and iPod Touch 2nd generation through 4th generation.{{cite web |last=Holt |first=Chris |url=https://www.macworld.com/article/207470/ios-gamecenter.html |title=iOS 4.1's GameCenter to Hit iPhone Next Week |website=Macworld |date=September 1, 2010 |access-date=February 21, 2022 |archive-date=February 22, 2022 |archive-url=https://web.archive.org/web/20220222020825/https://www.macworld.com/article/207470/ios-gamecenter.html |url-status=live }} Game Center made its public debut on the iPad with iOS 4.2.1.{{cite web|title=iOS 4.2 Software Update for iPad|url=https://support.apple.com/kb/DL1060|publisher=Apple Inc.|access-date=October 9, 2012|url-status=live|archive-url=https://web.archive.org/web/20130306014058/http://support.apple.com/kb/dl1060|archive-date=March 6, 2013}} There is no support for the iPhone 3G, original iPhone and the first-generation iPod Touch (the latter two devices did not have Game Center because they did not get iOS 4).{{cite web|url=https://www.apple.com/game-center|title=Game Center|date=December 23, 2010|publisher=Apple|archive-url=https://web.archive.org/web/20101223055005/https://www.apple.com/game-center|archive-date=December 23, 2010|url-status=dead}} However, Game Center is unofficially available on the iPhone 3G via a hack.{{cite web|url=https://www.shoutpedia.com/how-to-enable-game-centre-iphone-3g/|title=How to Install Game Center on iPhone 3G [Guide]|author=A. Usman|date=October 31, 2012|website=Shoutpedia|access-date=December 12, 2018|archive-date=December 15, 2018|archive-url=https://web.archive.org/web/20181215222557/https://www.shoutpedia.com/how-to-enable-game-centre-iphone-3g/|url-status=live}}

The main hardware platform for iOS is the ARM architecture (the ARMv7, ARMv8-A, ARMv8.2-A, ARMv8.3-A). iOS releases before iOS 7 can only be run on iOS devices with 32-bit ARM processors (ARMv6 and ARMv7-A architectures). In 2013, iOS 7 was released with full 64-bit support (which includes a native 64-bit kernel, libraries, drivers as well as all built-in applications),{{cite web |last=Wollman |first=Dana |url=https://www.engadget.com/2013/09/10/ios-7-64-bit/ |title=iOS 7 will be 64-bit, just like the iPhone 5s' new A7 chip |publisher=Engadget |date=September 10, 2013 |url-status=live |archive-url=https://web.archive.org/web/20150924141559/http://www.engadget.com/2013/09/10/ios-7-64-bit/ |archive-date=September 24, 2015 }} after Apple announced that they were switching to 64-bit ARMv8-A processors with the introduction of the Apple A7 chip.{{cite web |last=Souppouris |first=Aaron |url=https://www.theverge.com/2013/9/12/4722470/iphone-5s-64-bit-processor-is-a-bigger-deal-than-you-think |title=Why Apple's 64-bit iPhone chip is a bigger deal than you think |publisher=The Verge |date=September 12, 2013 |url-status=live |archive-url=https://web.archive.org/web/20170428174943/http://www.theverge.com/2013/9/12/4722470/iphone-5s-64-bit-processor-is-a-bigger-deal-than-you-think |archive-date=April 28, 2017 }} 64-bit support was also enforced for all apps in the App Store; All new apps submitted to the App Store with a deadline of February 2015, and all app updates submitted to the App Store with a deadline of June 1, 2015.{{cite web |last=Cunningham |first=Andrew |url=https://arstechnica.com/apple/2015/07/the-state-of-the-64-bit-transition-in-ios-and-whats-left-to-be-done/ |title=The state of the 64-bit transition in iOS, and what's left to be done |publisher=Ars Technica |date=July 2, 2015 |url-status=live |archive-url=https://web.archive.org/web/20170131202530/https://arstechnica.com/apple/2015/07/the-state-of-the-64-bit-transition-in-ios-and-whats-left-to-be-done/ |archive-date=January 31, 2017 }} iOS 11 drops support for all iOS devices with 32-bit ARM processors as well as 32-bit applications,{{cite web |last=Cunningham |first=Andrew |url=https://arstechnica.com/apple/2017/06/goodbye-32-bit-ios-11-ends-support-for-the-iphone-5-and-the-ipad-4/ |title=iOS 11 drops the iPhone 5 and 5C and the fourth-gen iPad |publisher=Ars Technica |date=June 5, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170605192202/https://arstechnica.com/apple/2017/06/goodbye-32-bit-ios-11-ends-support-for-the-iphone-5-and-the-ipad-4/ |archive-date=June 5, 2017 }}{{cite web |last=Mayo |first=Benjamin |url=https://9to5mac.com/2017/06/06/ios-11-32-bit-mac-app-store-64-bit/ |title=32-bit apps will not launch on iOS 11, Mac App Store transition to 64-bit from 2018 |publisher=9to5Mac |date=June 6, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170620040920/https://9to5mac.com/2017/06/06/ios-11-32-bit-mac-app-store-64-bit/ |archive-date=June 20, 2017 }} making iOS 64-bit only.{{cite web |last=Cunningham |first=Andrew |url=https://arstechnica.com/apple/2017/04/what-the-death-of-32-bit-ios-could-mean-for-apples-hardware-and-software/ |title=What the death of 32-bit iOS could mean for Apple's hardware and software |publisher=Ars Technica |date=April 13, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170429003555/https://arstechnica.com/apple/2017/04/what-the-death-of-32-bit-ios-could-mean-for-apples-hardware-and-software/ |archive-date=April 29, 2017 }}

{{Main|iOS SDK}}

The iOS software development kit (SDK) allows for the development of mobile apps that can run on iOS.

While originally developing iPhone prior to its unveiling in 2007, Apple's then-CEO Steve Jobs did not intend to let third-party developers build native apps for iOS, instead directing them to make web applications for the Safari web browser.{{cite web |title=Jobs' original vision for the iPhone: No third-party native apps |url=https://9to5mac.com/2011/10/21/jobs-original-vision-for-the-iphone-no-third-party-native-apps/ |website=9to5Mac |date=October 21, 2011 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170611063324/https://9to5mac.com/2011/10/21/jobs-original-vision-for-the-iphone-no-third-party-native-apps/ |archive-date=June 11, 2017 }} However, backlash from developers prompted the company to reconsider, with Jobs announcing in October 2007 that Apple would have a software development kit available for developers by February 2008.{{cite web |first=Geoff |last=Duncan |title=Apple confirms iPhone SDK coming next year |url=https://www.digitaltrends.com/apple/apple-confirms-iphone-sdk-coming-next-year/ |website=Digital Trends |date=October 17, 2007 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170828010954/https://www.digitaltrends.com/apple/apple-confirms-iphone-sdk-coming-next-year/ |archive-date=August 28, 2017 }}{{cite web |title=Steve Jobs confirms native iPhone SDK by February |url=http://appleinsider.com/articles/07/10/17/steve_jobs_confirms_native_iphone_sdk_by_february |website=AppleInsider |date=October 17, 2007 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170828020104/http://appleinsider.com/articles/07/10/17/steve_jobs_confirms_native_iphone_sdk_by_february |archive-date=August 28, 2017 }} The SDK was released on March 6, 2008.{{cite web |first=Jim |last=Dalrymple |title=Apple unveils iPhone SDK |url=http://www.macworld.com/article/1132400/iphonesdk.html |website=Macworld |publisher=International Data Group |date=March 6, 2008 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170828015010/http://www.macworld.com/article/1132400/iphonesdk.html |archive-date=August 28, 2017 }}{{cite web |first=Ryan |last=Block |author-link=Ryan Block |title=Live from Apple's iPhone SDK press conference |url=https://www.engadget.com/2008/03/06/live-from-apples-iphone-press-conference/ |website=Engadget |publisher=AOL |date=March 6, 2008 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170614212140/https://www.engadget.com/2008/03/06/live-from-apples-iphone-press-conference/ |archive-date=June 14, 2017 }}

The SDK is a free download for users of Mac personal computers.{{cite web |first=Jennifer |last=Guevin |title=FAQ: What does the iPhone SDK mean? |url=https://www.cnet.com/news/faq-what-does-the-iphone-sdk-mean/ |website=CNET |publisher=CBS Interactive |date=March 6, 2008 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160913135508/http://www.cnet.com/news/faq-what-does-the-iphone-sdk-mean/ |archive-date=September 13, 2016 }} It is not available for Microsoft Windows PCs. The SDK contains sets giving developers access to various functions and services of iOS devices, such as hardware and software attributes.{{cite web |first=Arnold |last=Kim |title=Apple Releases iPhone SDK, Demos Spore, Instant Messaging |url=https://www.macrumors.com/2008/03/06/apple-releases-iphone-sdk-demos-spore-instant-messaging/ |website=MacRumors |date=March 6, 2008 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160311195044/http://www.macrumors.com/2008/03/06/apple-releases-iphone-sdk-demos-spore-instant-messaging/ |archive-date=March 11, 2016 }} It also contains an iPhone simulator to mimic the look and feel of the device on the computer while developing. New versions of the SDK accompany new versions of iOS.{{cite web |first=Benjamin |last=Mayo |title=Apple now allowing developers to submit iOS 9, OS X El Capitan and native Watch apps to the App Store |url=https://9to5mac.com/2015/09/11/apple-developers-os-9-apps/ |website=9to5Mac |date=September 11, 2015 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160822090552/https://9to5mac.com/2015/09/11/apple-developers-os-9-apps/ |archive-date=August 22, 2016 }}{{cite web |first=Steven |last=Sande |title=New iOS SDK features for developers |url=https://www.engadget.com/2013/06/10/new-ios-sdk-features-for-developers/ |website=Engadget |publisher=AOL |date=June 10, 2013 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20180115215751/https://www.engadget.com/2013/06/10/new-ios-sdk-features-for-developers/ |archive-date=January 15, 2018 }} In order to test applications, get technical support, and distribute apps through App Store, developers are required to subscribe to the Apple Developer Program.

Combined with Xcode, the iOS SDK helps developers write iOS apps using officially supported programming languages, including Swift and Objective-C.{{cite web |first=Adam |last=Sinicki |title=Developing for Android vs developing for iOS – in 5 rounds |url=http://www.androidauthority.com/developing-for-android-vs-ios-697304/ |website=Android Authority |date=June 9, 2016 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170626191841/http://www.androidauthority.com/developing-for-android-vs-ios-697304/ |archive-date=June 26, 2017 }} Other companies have also created tools that allow for the development of native iOS apps using their respective programming languages.{{cite web |first=Ryan |last=Paul |title=MonoTouch drops .NET into Apple's walled app garden |url=https://arstechnica.com/information-technology/2009/09/monotouch-drops-net-into-apples-walled-app-garden/ |website=Ars Technica |date=September 15, 2009 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20151122123311/http://arstechnica.com/information-technology/2009/09/monotouch-drops-net-into-apples-walled-app-garden/ |archive-date=November 22, 2015 }}{{cite web |first=Jackie |last=Dove |title=Adobe unleashes Creative Suite 5 |url=http://www.macworld.com/article/1150522/cs5launch.html |website=Macworld |publisher=International Data Group |date=April 11, 2010 |access-date=June 21, 2017 |url-status=live |archive-url=https://web.archive.org/web/20140924005201/http://www.macworld.com/article/1150522/cs5launch.html |archive-date=September 24, 2014 }}

{{Main|iOS version history|Issues relating to iOS}}

{{pie chart

| thumb = right

| caption = iPhone platform usage as measured by the App Store on January 21th, 2025{{Cite web|url=https://developer.apple.com/support/app-store/|title=App Store – Support – Apple Developer|website=Apple Developer|access-date=January 26, 2022|archive-date=November 1, 2017|archive-url=https://web.archive.org/web/20171101233112/https://developer.apple.com/support/app-store/|url-status=live}}

| label1 = iOS 18

| value1 = 76

| color1 = #79CDF8

| label2 = iOS 17

| value2 = 19

| color2 = #B3E1FB

| label3 = iOS 16 and earlier

| value3 = 5

| color3 = #FFFFFF

}}

{{pie chart

| thumb = right

| caption = iPad platform usage as measured by the App Store on January 21th, 2025

| label1 = iPadOS 18

| value1 = 63

| color1 = #F7A379

| label2 = iPadOS 17

| value2 = 27

| color2 = #FACCB1

| label3 = iPadOS 16 and earlier

| value3 = 10

| color3 = #FFFFFF

}}

Apple provides major updates to the iOS operating system annually via iTunes and, since iOS 5, also over-the-air.{{cite web|last=Caldwell|first=Serenity|date=October 15, 2011|title=Up close with iOS 5: Wireless syncing and updating|url=http://www.macworld.com/article/1163060/up_close_with_ios_5_wireless_syncing_and_updating.html|url-status=live|archive-url=https://web.archive.org/web/20170808112956/http://www.macworld.com/article/1163060/up_close_with_ios_5_wireless_syncing_and_updating.html|archive-date=August 8, 2017|access-date=June 20, 2017|website=Macworld|publisher=International Data Group}} The device checks an XML-based PLIST file on mesu.apple.com {{Citation needed|date=October 2023}} for updates. Updates are delivered as unencrypted ZIP files. Updates are checked for regularly, and are downloaded and installed automatically if enabled. Otherwise, the user can install them manually or are prompted to allow automatic installation overnight if plugged in and connected to Wi-Fi.

iPod Touch users originally had to pay for system software updates due to accounting rules that designated it not a "subscription device" like the iPhone or Apple TV,{{cite web|date=January 15, 2008|title=About that $20 upgrade...|url=https://www.cnet.com/news/about-that-20-upgrade/|url-status=live|archive-url=https://web.archive.org/web/20171031215628/https://www.cnet.com/news/about-that-20-upgrade/|archive-date=October 31, 2017|access-date=June 20, 2017|website=CNET|publisher=CBS Interactive}}{{cite web|last=Dalrymple|first=Jim|date=February 7, 2008|title=Accounting rules behind iPod Touch update charge|url=https://www.macworld.com/article/189247/ipodtouch-3.html|access-date=February 16, 2022|website=Macworld|publisher=International Data Group|archive-date=February 16, 2022|archive-url=https://web.archive.org/web/20220216222015/https://www.macworld.com/article/189247/ipodtouch-3.html|url-status=live}} causing many iPod Touch owners not to update.{{cite web|last=Oliver|first=Sam|date=June 25, 2009|title=Upgrade fee sees few iPod Touch users updating to 3.0 software|url=http://appleinsider.com/articles/09/06/25/upgrade_fee_sees_few_ipod_touch_users_updating_to_3_0_software|url-status=live|archive-url=https://web.archive.org/web/20170305192021/http://appleinsider.com/articles/09/06/25/upgrade_fee_sees_few_ipod_touch_users_updating_to_3_0_software|archive-date=March 5, 2017|access-date=June 20, 2017|website=AppleInsider}} In September 2009, a change in accounting rules won tentative approval, affecting Apple's earnings and stock price, and allowing iPod Touch updates to be delivered free of charge.{{cite web|last=Foresman|first=Chris|date=September 14, 2009|title=Accounting rules change could end iPod Touch update fee|url=https://arstechnica.com/apple/2009/09/accounting-rules-change-could-end-ipod-touch-update-fee/|url-status=live|archive-url=https://web.archive.org/web/20170708034000/https://arstechnica.com/apple/2009/09/accounting-rules-change-could-end-ipod-touch-update-fee/|archive-date=July 8, 2017|access-date=June 20, 2017|website=Ars Technica}}{{cite web|last=Elmer-DeWitt|first=Philip|date=September 14, 2009|title=Accounting rule change in Apple's favor|url=http://fortune.com/2009/09/14/accounting-rule-change-in-apples-favor/|url-status=live|archive-url=https://web.archive.org/web/20170711122406/http://fortune.com/2009/09/14/accounting-rule-change-in-apples-favor/|archive-date=July 11, 2017|access-date=June 20, 2017|website=Fortune}}

Apple significantly extended the cycle of updates for iOS-supported devices over the years. The iPhone (1st generation) and iPhone 3G only received two iOS updates, while later models had support for five, six, and seven years.{{Cite web|title=Infographic: How Long Does Apple Support Older iPhone Models?|url=https://www.statista.com/chart/5824/ios-iphone-compatibility/|access-date=August 11, 2020|website=Statista Infographics|archive-date=August 7, 2020|archive-url=https://web.archive.org/web/20200807035858/https://www.statista.com/chart/5824/ios-iphone-compatibility/|url-status=live}}{{Cite web|date=July 3, 2019|title=Here's how long Apple supports older iPhone models|url=https://www.imore.com/apples-continual-software-support-iphones-major-reason-theyre-popular|access-date=August 11, 2020|website=iMore|archive-date=August 18, 2020|archive-url=https://web.archive.org/web/20200818214108/https://www.imore.com/apples-continual-software-support-iphones-major-reason-theyre-popular|url-status=live}}

{{Main|XNU}}

The iOS kernel is the XNU kernel of Darwin. The original iPhone OS (1.0) up to iPhone OS 3.1.3 used Darwin 9.0.0d1. iOS 4 was based on Darwin 10. iOS 5 was based on Darwin 11. iOS 6 was based on Darwin 13. iOS 7 and iOS 8 are based on Darwin 14. iOS 9 is based on Darwin 15. iOS 10 is based on Darwin 16. iOS 11 is based on Darwin 17. iOS 12 is based on Darwin 18. iOS 13 is based on Darwin 19. iOS 14 is based on Darwin 20. iOS 15 is based on Darwin 21. iOS 16 is based on Darwin 22.Available in iOS 5 to iOS 7 via General > About > Diagnostics & Usage > Diagnostics & Usage Data >(date and time).panic.plist, after a kernel crash
Available in iOS 8 to iOS 10 via Privacy > Diagnostics & Usage > Diagnostics & Usage Data > JetsamEvent-(date and time).ips, when low in memory
Available in iOS 11 and 12 via Privacy > Analytics > Analytics Data > JetsamEvent-(date and time).ips, when low in memory
Available in iOS 13 via Privacy > Analytics & Improvements > Analytics Data > SystemMemoryReset-(date and time).ips, when low in memory

In iOS 6 the kernel is subject to ASLR, similar to that of OS X Mountain Lion. This makes exploit possibilities more complex since it is not possible to know the location of kernel code.

Apple has made the XNU kernel open source.{{Cite web|url=https://opensource.apple.com/source/xnu/|title=Source Browser|website=Apple Open Source |access-date=March 3, 2021|archive-date=February 18, 2018|archive-url=https://web.archive.org/web/20180218095814/https://opensource.apple.com/source/xnu/|url-status=live}} The source is under a 3-clause{{Cite web|url=https://opensource.org/licenses/BSD-3-Clause|title=The 3-Clause BSD License |website=Open Source Initiative |date=May 22, 2011 |access-date=March 3, 2021|archive-date=March 3, 2021|archive-url=https://web.archive.org/web/20210303132019/https://opensource.org/licenses/BSD-3-Clause|url-status=live}} BSD license for the original BSD parts, with parts added by Apple under the Apple Public Source License.{{Cite web|url=https://images.apple.com/publicsource/pdf/apple-public-source-license.pdf|title=Apple Public Source License, Version 1.0|date=March 16, 1999 |access-date=March 3, 2021|archive-date=August 14, 2021|archive-url=https://web.archive.org/web/20210814035339/https://images.apple.com/publicsource/pdf/apple-public-source-license.pdf|url-status=dead }} The versions contained in iOS are not available; only the versions used in macOS are available.

iOS does not have kernel extensions (kexts) in the file system, even if they are actually present. The kernel cache can be decompressed to show the correct kernel, along with the kexts (all packed in the __PRELINK_TEXT section) and their plists (in the __PRELINK_INFO section).

The kernel cache can also be directly decompressed (if decrypted) using third-party tools. With the advent of iOS 10 betas and default plain text kernelcaches, these tools can only be used after unpacking and applying lzssdec to unpack the kernel cache to its full size.

The kextstat provided by the Cydia alternative software does not work on iOS because the kextstat is based on kmod_get_info(...), which is a deprecated API in iOS 4 and Mac OS X Snow Leopard. There are other alternative software that can also dump raw XML data.

On developing devices, the kernel is always stored as a statically linked cache stored in /System/Library/Caches/com.apple.kernelcaches/kernelcache which is unpacked and executed at boot.

In the beginning, iOS had a kernel version usually higher than the corresponding version of macOS. Over time, the kernels of iOS and macOS have gotten closer. This is not surprising, considering that iOS introduced new features (such as the ASLR Kernel, the default freezer, and various security-strengthening features) that were first incorporated and subsequently arrived on macOS. It appears Apple is gradually merging the iOS and macOS kernels over time. The build date for each version varies slightly between processors. This is due to the fact that the builds are sequential.

{{Main|iOS jailbreaking}}{{More citations needed|section|date=February 2024}}

Since its initial release, iOS has been subject to a variety of different hacks centered around adding functionality not allowed by Apple.{{cite web |first=Thomas |last=Ricker |title=iPhone Hackers: "we have owned the filesystem" |url=https://www.engadget.com/2007/07/10/iphone-hackers-we-have-owned-the-filesystem/ |website=Engadget |publisher=AOL |date=July 10, 2007 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170401233052/https://www.engadget.com/2007/07/10/iphone-hackers-we-have-owned-the-filesystem/ |archive-date=April 1, 2017 }} Prior to the 2008 debut of Apple's native iOS App Store, the primary motive for jailbreaking was to bypass Apple's purchase mechanism for installing the App Store's native applications.{{cite news|last=Healey|first=Jon|title=Hacking the iPhone|work=Los Angeles Times|date=August 6, 2007|url=http://www.latimes.com/news/opinion/la-oew-healey6aug06,0,3456267.story|access-date=August 6, 2007|url-status=live|archive-url=https://web.archive.org/web/20071106035917/http://www.latimes.com/news/opinion/la-oew-healey6aug06,0,3456267.story|archive-date=November 6, 2007}} Apple claimed that it would not release iOS software updates designed specifically to break these tools (other than applications that perform SIM unlocking); however, with each subsequent iOS update, previously un-patched jailbreak exploits are usually patched.{{cite web |url= https://www.geek.com/apple/apples-joswiak-we-dont-hate-iphone-coders-1374199/ |title= Apple's Joswiak: We Don't Hate iPhone Coders |date= September 11, 2007 |access-date= February 19, 2017 |url-status=live |archive-url= https://web.archive.org/web/20170220092613/https://www.geek.com/apple/apples-joswiak-we-dont-hate-iphone-coders-1374199/ |archive-date= February 20, 2017 |df= mdy-all }}

When a device is booting, it loads Apple's own kernel initially,{{Cite web |title=What you need to know about iOS jailbreaks - Promon |url=https://promon.co/security-news/what-you-need-to-know-about-ios-jailbreaks |access-date=2024-05-31 |website=promon.co |language=en |archive-date=August 25, 2024 |archive-url=https://web.archive.org/web/20240825065819/https://promon.co/security-news/what-you-need-to-know-about-ios-jailbreaks |url-status=live }}{{Cite web |title=Types of Jailbreak {{!}} iOS Guide |url=https://ios.cfw.guide/types-of-jailbreak/ |access-date=2024-05-31 |website=ios.cfw.guide |archive-date=May 31, 2024 |archive-url=https://web.archive.org/web/20240531184251/https://ios.cfw.guide/types-of-jailbreak/ |url-status=live }} so a jailbroken device must be exploited and have the kernel patched each time it is booted up.

There are different types of jailbreak. An untethered jailbreak uses exploits that are powerful enough to allow the user to turn their device off and back on at will, with the device starting up completely, and the kernel will be patched without the help of a computer – in other words, it will be jailbroken even after each reboot.

However, some jailbreaks are tethered. A tethered jailbreak is only able to temporarily jailbreak the device during a single boot. If the user turns the device off and then boots it back up without the help of a jailbreak tool, the device will no longer be running a patched kernel, and it may get stuck in a partially started state, such as Recovery Mode. In order for the device to start completely and with a patched kernel, it must be "re-jailbroken" with a computer (using the "boot tethered" feature of a tool) each time it is turned on. All changes to the files on the device (such as installed package files or edited system files) will persist between reboots, including changes that can only function if the device is jailbroken (such as installed package files).{{Cite web |last=Bouchard |first=Anthony |date=2019-11-22 |title=Understanding untethered, semi-untethered, semi-tethered, and tethered jailbreaks |url=https://www.idownloadblog.com/2019/11/21/types-of-jailbreaks/ |access-date=2024-05-31 |website=iDownloadBlog.com |language=en-US |archive-date=November 22, 2019 |archive-url=https://web.archive.org/web/20191122153719/https://www.idownloadblog.com/2019/11/21/types-of-jailbreaks/ |url-status=live }}

In more recent years, two other solutions have been created – semi-tethered and semi-untethered.

A semi-tethered solution is one where the device is able to start up on its own, but it will no longer have a patched kernel, and therefore will not be able to run modified code. It will, however, still be usable for normal functions, just like stock iOS. To start with a patched kernel, the user must start the device with the help of the jailbreak tool.

A semi-untethered jailbreak gives the ability to start the device on its own. On first boot, the device will not be running a patched kernel. However, rather than having to run a tool from a computer to apply the kernel patches, the user is able to re-jailbreak their device with the help of an app (usually sideloaded using Cydia Impactor) running on their device. In the case of the iOS 9.2-9.3.3 and 64-bit 10.x jailbreaks, Safari-based exploits were available, thereby meaning websites could be used to re-jailbreak.

In more detail: Each iOS device has a bootchain that tries to make sure only trusted/signed code is loaded. A device with a tethered jailbreak is able to boot up with the help of a jailbreaking tool because the tool executes exploits via USB that bypass parts of that "chain of trust", bootstrapping to a pwned (no signature check) iBEC, or iBoot to finish the boot process.

Since the arrival of Apple's native iOS App Store, and—along with it—third-party applications, the general motives for jailbreaking have changed.{{cite news |url= https://www.usatoday.com/tech/columnist/edwardbaig/2007-06-26-iphone-review_N.htm |title= Apple's iPhone isn't perfect, but it's worthy of the hype |author= Baig, Edward C. |work= USA Today |date= June 26, 2007 |access-date= June 28, 2007 |url-status=live |archive-url= https://web.archive.org/web/20070629012206/http://www.usatoday.com/tech/columnist/edwardbaig/2007-06-26-iphone-review_N.htm |archive-date= June 29, 2007 |df= mdy-all }} People jailbreak for many different reasons, including gaining filesystem access, installing custom device themes, and modifying SpringBoard. An additional motivation is that it may enable the installation of pirated apps. On some devices, jailbreaking also makes it possible to install alternative operating systems, such as Android and the Linux kernel. Primarily, users jailbreak their devices because of the limitations of iOS. Depending on the method used, the effects of jailbreaking may be permanent or temporary.{{cite web

|last = IPad

|first = MAX

|title = Jailbreaking Explained

|publisher = IPad Forums

|date = May 6, 2010

|url = http://www.ipadforums.net/ipad-hacking/2838-jailbreaking-explained.html

|access-date = November 4, 2012

|url-status = live

|archive-url = https://web.archive.org/web/20121102053916/http://www.ipadforums.net/ipad-hacking/2838-jailbreaking-explained.html

|archive-date = November 2, 2012

|df = mdy-all

}}

In 2010, the Electronic Frontier Foundation (EFF) successfully convinced the U.S. Copyright Office to allow an exemption to the general prohibition on circumvention of copyright protection systems under the Digital Millennium Copyright Act (DMCA). The exemption allows jailbreaking of iPhones for the sole purpose of allowing legally obtained applications to be added to the iPhone.{{cite magazine|url= https://www.wired.com/threatlevel/2010/07/feds-ok-iphone-jailbreaking/|title= U.S. Declares iPhone Jailbreaking Legal, Over Apple's Objections|author= Kravets, David|magazine= Wired|date= July 26, 2010|access-date= December 13, 2011|url-status=live|archive-url= https://web.archive.org/web/20120803003029/http://www.wired.com/threatlevel/2010/07/feds-ok-iphone-jailbreaking/|archive-date= August 3, 2012|df= mdy-all}} The exemption does not affect the contractual relations between Apple and an iPhone owner, for example, jailbreaking voiding the iPhone warranty; however, it is solely based on Apple's discretion on whether they will fix jailbroken devices in the event that they need to be repaired. At the same time, the Copyright Office exempted unlocking an iPhone from DMCA's anticircumvention prohibitions.{{cite web|url= http://www.copyright.gov/fedreg/2010/75fr43825.pdf|title= U.S. Copyright Office Final 2010 Anti-Circumvention Rulemaking|publisher= U.S. Copyright Office|date= July 27, 2010|access-date= August 21, 2012|url-status=live|archive-url= https://web.archive.org/web/20120501085441/http://www.copyright.gov/fedreg/2010/75fr43825.pdf|archive-date= May 1, 2012|df= mdy-all}} Unlocking an iPhone allows the iPhone to be used with any wireless carrier using the same GSM or CDMA technology for which the particular phone model was designed to operate.{{cite web

|last = Mobile

|first = Know Your

|title = Locked / Unlocked – a definition of the terms Locked and Unlocked from the Know Your Mobile mobile phone glossary

|publisher = Know Your Mobile

|date = May 19, 2010

|url = http://www.knowyourmobile.com/glossary/l/488285/locked_unlocked.html

|access-date = November 4, 2012

|url-status = dead

|archive-url = https://web.archive.org/web/20120831061738/http://www.knowyourmobile.com/glossary/l/488285/locked_unlocked.html

|archive-date = August 31, 2012

|df = mdy-all

}}

{{Main|SIM lock}}

Initially most wireless carriers in the US did not allow iPhone owners to unlock it for use with other carriers. However AT&T allowed iPhone owners who had satisfied contract requirements to unlock their iPhone.{{cite web|url=http://www.att.com/esupport/article.jsp?sid=KB414532|title=AT&T – What are the eligibility requirements for unlocking iPhone?|publisher=AT&T|archive-url=https://web.archive.org/web/20120803185724/https://www.att.com/esupport/article.jsp?sid=KB414532|archive-date=August 3, 2012}} Instructions to unlock the device are available from Apple,{{cite web|url=http://support.apple.com/kb/HT5014|title=iPhone: About unlocking|publisher=Apple Inc. Website|date=March 4, 2021|url-status=live|archive-url=https://web.archive.org/web/20121017021001/http://support.apple.com/kb/HT5014|archive-date=October 17, 2012}} but it is ultimately at the sole discretion of the carrier to authorize unlocking the device.{{cite web|url=http://support.apple.com/kb/ht1937|title=iPhone: Wireless Carrier Support and Features|publisher=Apple Inc. Website|date=April 12, 2013|access-date=May 13, 2013|url-status=live|archive-url=https://web.archive.org/web/20130424042251/http://support.apple.com/kb/HT1937|archive-date=April 24, 2013}} This allows the use of a carrier-sourced iPhone on other networks. Modern versions of iOS and the iPhone fully support LTE across multiple carriers wherever the phone was purchased.{{cite news|url= https://www.macworld.com/article/2991494/carriers/new-iphones-use-lte-on-any-american-carrier-despite-the-way-theyre-listed.html|title= New iPhones use LTE on any American carrier, despite the way they're listed|first=Glenn|last=Fleishman|work= MacWorld|date= October 9, 2015|url-status=live|archive-url= https://web.archive.org/web/20170713084749/http://www.macworld.com/article/2991494/carriers/new-iphones-use-lte-on-any-american-carrier-despite-the-way-theyre-listed.html|archive-date= July 13, 2017|df= mdy-all}} Programs to remove SIM lock restrictions are available, but are not supported by Apple, and most often not a permanent unlock – a soft unlock,{{cite web|url=http://support.apple.com/kb/HT3743|title=Unauthorized modification of iOS can cause security vulnerabilities, instability, shortened battery life, and other issues|publisher=Apple Inc.|date=June 15, 2018|url-status=live|archive-url=https://web.archive.org/web/20130510123825/http://support.apple.com/kb/HT3743|archive-date=May 10, 2013}} which modifies the iPhone so that the baseband will accept the SIM card of any GSM carrier. SIM unlocking is not jailbreaking, but a jailbreak is also required for these unofficial software unlocks.

The legality of software unlocking varies in each country; for example, in the US, there is a DMCA exemption for unofficial software unlocking of devices purchased before January 26, 2013.{{Cite report|title=Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies|url=https://www.copyright.gov/fedreg/2012/2012-26308_PI.pdf|id=37 CFR Part 201 [Docket No. 2011-7]|date=October 26, 2012|publisher=United States Copyright Office|access-date=September 4, 2020|archive-date=September 25, 2020|archive-url=https://web.archive.org/web/20200925074248/https://www.copyright.gov/fedreg/2012/2012-26308_PI.pdf|url-status=live}}

{{Essay-like|date=January 2025|section}}

The closed and proprietary nature of iOS has garnered criticism, particularly by digital rights advocates such as the Electronic Frontier Foundation, computer engineer and activist Brewster Kahle, Internet-law specialist Jonathan Zittrain, and the Free Software Foundation who protested the iPad's introductory event and have targeted the iPad with their "Defective by Design" campaign.{{cite web |url= https://www.defectivebydesign.org/ipad |title= Tell Tim Cook: No more DRM for Apple |access-date= September 4, 2020 |website= Defective by Design |archive-date= September 20, 2020 |archive-url= https://web.archive.org/web/20200920090650/https://www.defectivebydesign.org/ipad |url-status= live }}{{cite web |first=Nate |last=Anderson |title=Protestors: iPad is nothing more than a golden calf of DRM |url=https://arstechnica.com/tech-policy/2010/01/protestors-ipad-is-nothing-more-than-a-golden-calf-of-drm/ |website=Ars Technica |date=January 27, 2010 |access-date=April 1, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170402081221/https://arstechnica.com/tech-policy/2010/01/protestors-ipad-is-nothing-more-than-a-golden-calf-of-drm/ |archive-date=April 2, 2017 }}{{cite web |url= http://thedianerehmshow.org/shows/2010-02-03/mobile-devices-and-next-computing-revolution-0 |title= Mobile Devices and the Next Computing Revolution |date= February 3, 2010 |access-date= June 9, 2010 |url-status=live |archive-url= https://web.archive.org/web/20101201053215/http://thedianerehmshow.org/shows/2010-02-03/mobile-devices-and-next-computing-revolution-0 |archive-date= December 1, 2010 |df= mdy-all }}{{cite news |url= https://www.theguardian.com/technology/2010/feb/01/apple-ipad-choke-innovation |title= Apple iPad will choke innovation, say open internet advocates |work= The Guardian |date= February 1, 2010 |author= Bobbie Johnson |access-date= February 7, 2010 |url-status=live |archive-url= https://web.archive.org/web/20140316141036/http://www.theguardian.com/technology/2010/feb/01/apple-ipad-choke-innovation |archive-date= March 16, 2014 |df= mdy-all }} Competitor Microsoft, via a PR spokesman, criticized Apple's control over its platform.{{cite web |url= http://technologizer.com/2010/01/28/microsoft-ipads-closed-platfor-is-humorous/ |title= Microsoft PR spokesman condemns iPad for being "locked down" |date= January 29, 2010 |url-status=live |archive-url= https://web.archive.org/web/20120305021357/http://technologizer.com/2010/01/28/microsoft-ipads-closed-platfor-is-humorous/ |archive-date= March 5, 2012 |df= mdy-all }}

At issue are restrictions imposed by the design of iOS, namely digital rights management (DRM) intended to lock purchased media to Apple's platform, the development model (requiring a yearly subscription to distribute apps developed for the iOS), the centralized approval process for apps, as well as Apple's general control and lockdown of the platform itself. Particularly at issue is the ability for Apple to remotely disable or delete apps at will.{{Cite web |last=McSherry |first=Corynne |date=2015-01-07 |title=Sorry iPhone Users: Apple's Dev Agreement Means No EFF Mobile App for iOS |url=https://www.eff.org/deeplinks/2014/12/sorry-iphone-users-apples-dev-agreement-means-no-eff-mobile-app-iphone |access-date=2023-11-16 |website=Electronic Frontier Foundation |language=en}}

Some{{Who|date=January 2025}} in the tech community have expressed concern that the locked-down iOS represents a growing trend in Apple's approach to computing, particularly Apple's shift away from machines that hobbyists can "tinker with" and note the potential for such restrictions to stifle software innovation.{{cite web |url= http://apple.slashdot.org/story/10/01/31/1657233/Apples-Trend-Away-From-Tinkering |title= Apple's Trend Away From Tinkering |publisher= Slashdot |date= January 31, 2010 |access-date= June 9, 2010 |url-status=live |archive-url= https://web.archive.org/web/20100208164828/http://apple.slashdot.org/story/10/01/31/1657233/Apples-Trend-Away-From-Tinkering |archive-date= February 8, 2010 |df= mdy-all }}{{cite video

|url = https://www.youtube.com/watch?v=JDrJd7GkkNA

|title = Campus Party Brasil 2011 – Geek Pride e Wozniak

|people = Steve Wozniak (Interviewee)

|date = January 22, 2011

|publisher = Fragoso, Victor

|access-date = March 7, 2011

|url-status = live

|archive-url = https://web.archive.org/web/20110512222742/http://www.youtube.com/watch?v=JDrJd7GkkNA

|archive-date = May 12, 2011

|df = mdy-all

}}

Former Facebook developer Joe Hewitt protested against Apple's control over its hardware as a "horrible precedent" but praised iOS's sandboxing of apps.{{cite web |url= http://www.cultofmac.com/pundits-on-the-ipads-closed-system-its-doom-for-pcs-no-its-great/28440 |title= Pundits On The iPad's Closed System: It's Doom For PCs, No It's Great |author= Leander Kahney |date= January 30, 2010 |access-date= June 9, 2010 |url-status=live |archive-url= https://web.archive.org/web/20100515124959/http://www.cultofmac.com/pundits-on-the-ipads-closed-system-its-doom-for-pcs-no-its-great/28440 |archive-date= May 15, 2010 |df= mdy-all }}

{{Main article|Security and privacy of iOS}}

{{expand section|date=March 2025}}

iOS utilizes many security features in both hardware and software.

{{See also|Usage share of operating systems}}{{bar box

|float=right

|title=Worldwide market share of smartphone operating systems

|titlebar=#DDD

|width=350px

|barwidth=250px

|bars={{bar percent|Android|#A3FFA3|67.72|67.72%}}

{{bar percent|iOS|#A3D3FF|31.44|31.44%}}

{{bar percent|Other|#A3D3FF|0.84|0.84%}}

{{bar gap|height=11}}

|caption=Source: Statcounter ({{as of|2023|05|bare=y|df=us}}).{{Cite web |url=https://gs.statcounter.com/os-market-share/mobile/worldwide/#monthly-202205-202305/ |title=Mobile Operating System Market Share Worldwide |website=Statcounter |language=en |access-date=June 10, 2022 |archive-date=February 22, 2023 |archive-url=https://web.archive.org/web/20230222212255/https://gs.statcounter.com/os-market-share/mobile/worldwide#monthly-202205-202305/ |url-status=live }}

}}

iOS is the second most popular mobile operating system in the world, after Android. Sales of iPads in recent years are also behind Android, while, by web use (a proxy for all use), iPads (using iOS) are still the most popular.{{cite web|title=StatCounter Global Stats – Browser, OS, Search Engine including Mobile Usage Share|url=https://gs.statcounter.com/#tablet-os-ww-monthly-201612-201612-map|access-date=September 4, 2020|website=StatCounter GlobalStats|archive-date=May 26, 2012|archive-url=https://archive.today/20120526/http://gs.statcounter.com/%23mobile_browser-ww-monthly-201012-201111-bar#tablet-os-ww-monthly-201612-201612-map|url-status=live}}

At WWDC 2014, Tim Cook said 800 million devices had been sold by June 2014.{{cite web|last=Ingraham|first=Nathan|date=June 2, 2014|title=Apple has sold more than 800 million iOS devices, 130 million new iOS users in the last year|url=https://www.theverge.com/2014/6/2/5772344/apple-wwdc-2014-stats-update|url-status=live|archive-url=https://web.archive.org/web/20170210135711/http://www.theverge.com/2014/6/2/5772344/apple-wwdc-2014-stats-update|archive-date=February 10, 2017|access-date=April 1, 2017|website=The Verge|publisher=Vox Media}} During Apple's quarterly earnings call in January 2015, the company announced that they had sold over one billion iOS devices since 2007.{{cite web|last=Rossignol|first=Joe|date=January 27, 2015|title=Tim Cook: Apple Has Sold More Than 1 Billion iOS Devices|url=https://www.macrumors.com/2015/01/27/apple-one-billion-ios-devices/|url-status=live|archive-url=https://web.archive.org/web/20160623144503/http://www.macrumors.com/2015/01/27/apple-one-billion-ios-devices/|archive-date=June 23, 2016|access-date=June 21, 2017|website=MacRumors}}{{cite web|last=Kahn|first=Jordan|date=January 27, 2015|title=Apple announces 1 billion iOS devices sold|url=https://9to5mac.com/2015/01/27/apple-announces-1-billion-ios-devices-sold/|url-status=live|archive-url=https://web.archive.org/web/20170704104006/https://9to5mac.com/2015/01/27/apple-announces-1-billion-ios-devices-sold/|archive-date=July 4, 2017|access-date=June 21, 2017|website=9to5Mac}}

By February 2023, there were 2 billion devices activated,{{Cite web |title=Apple actives devices 2023 |url=https://www.statista.com/statistics/1383887/number-of-apple-active-devices/ |access-date=2023-12-16 |website=Statista |language=en |archive-date=August 25, 2024 |archive-url=https://web.archive.org/web/20240825065858/https://www.statista.com/statistics/1383887/number-of-apple-active-devices/ |url-status=live }} and 1.5 billion iPhones had been sold since 2007.{{Cite web |title=Apple iPhone revenue by quarter 2023 |url=https://www.statista.com/statistics/263402/apples-iphone-revenue-since-3rd-quarter-2007/ |access-date=2023-12-16 |website=Statista |language=en |archive-date=December 16, 2023 |archive-url=https://web.archive.org/web/20231216142528/https://www.statista.com/statistics/263402/apples-iphone-revenue-since-3rd-quarter-2007/ |url-status=live }}

By late 2011, iOS accounted for 60% of the market share for smartphones and tablets.{{cite book|last=Saylor|first=Michael|title=The Mobile Wave: How Mobile Intelligence Will Change Everything|publisher=Vanguard Press|year=2012|isbn=978-1-59315-720-3|page=33}} By the end of 2014, iOS accounted for 14.8% of the smartphone market{{cite press release|url=http://www.idc.com/getdoc.jsp?containerId=prUS25450615|title=Android and iOS Squeeze the Competition, Swelling to 96.3% of the Smartphone Operating System Market for Both 4Q14 and CY14, According to IDC|publisher=IDC|date=February 24, 2015|archive-url=https://web.archive.org/web/20150225074430/http://www.idc.com/getdoc.jsp?containerId=prUS25450615|archive-date=February 25, 2015|url-status=dead}} and 27.6% of the tablet and two-in-one market.{{cite press release|url=http://www.idc.com/getdoc.jsp?containerId=prUS25480015|title=Worldwide Tablet Growth Hits the Brakes, Slowing to the Low Single Digits in the Years Ahead, According to IDC|publisher=IDC|date=March 12, 2015|archive-url=https://web.archive.org/web/20150313224458/http://www.idc.com/getdoc.jsp?containerId=prUS25480015|archive-date=March 13, 2015|url-status=dead}} In May 2023, StatCounter reported iOS was used on 31.44% of smartphones and 55.75% of tablets worldwide, measured by internet usage instead of sales.{{cite web|title=StatCounter Global Stats: Top 7 Mobile Operating Systems on Feb 2015|url=https://gs.statcounter.com/#tablet-os-ww-monthly-201502-201503-bar|access-date=September 4, 2020|website=StatCounter GlobalStats|archive-date=May 26, 2012|archive-url=https://archive.today/20120526/http://gs.statcounter.com/%23mobile_browser-ww-monthly-201012-201111-bar#tablet-os-ww-monthly-201502-201503-bar|url-status=live}}

In the third quarter of 2015, research from Strategy Analytics showed that iOS adoption of the worldwide smartphone market was at a record low 12.1%, attributed to lackluster performance in China and Africa. Android accounted for 87.5% of the market, with Windows Phone and BlackBerry accounting for the rest.{{cite web|last=Sui|first=Linda|date=November 2, 2016|title=Strategy Analytics: Android Captures Record 88 Percent Share of Global Smartphone Shipments in Q3 2016|url=https://www.strategyanalytics.com/strategy-analytics/news/strategy-analytics-press-releases/strategy-analytics-press-release/2016/11/02/strategy-analytics-android-captures-record-88-percent-share-of-global-smartphone-shipments-in-q3-2016#.WDqfU-YrKUl|url-status=live|archive-url=https://web.archive.org/web/20161127153018/https://www.strategyanalytics.com/strategy-analytics/news/strategy-analytics-press-releases/strategy-analytics-press-release/2016/11/02/strategy-analytics-android-captures-record-88-percent-share-of-global-smartphone-shipments-in-q3-2016#.WDqfU-YrKUl|archive-date=November 27, 2016|access-date=November 27, 2016|publisher=Strategy Analytics}}{{cite web|last=Rossignol|first=Joe|date=November 2, 2016|title=iOS Adoption Remains at Lowest Levels Since 2014 as Android Captures Record 87.5% Market Share|url=http://www.macrumors.com/2016/11/02/ios-vs-android-market-share-3q16/|url-status=live|archive-url=https://web.archive.org/web/20161127215126/http://www.macrumors.com/2016/11/02/ios-vs-android-market-share-3q16/|archive-date=November 27, 2016|access-date=November 27, 2016|publisher=MacRumors}}

{{Main|List of iPhone models}}

{{Timeline of iOS devices}}

{{portal|Computer programming}}

• Comparison of mobile operating systems

{{Reflist}}

{{Commons category|IOS (Apple Inc.)}}

• {{Official website|www.apple.com/ios}}
• [https://developer.apple.com/ios/ Official dev center website] at Apple Developer Connection
• [https://developer.apple.com/library/ios/navigation/ iOS Reference Library] – on the Apple Developer Connection website

{{iOS}}

{{iPod}}

{{Apple Inc. operating systems}}

{{Darwin derivations}}

{{Unix-like}}

{{Operating system}}

{{Mobile operating systems}}

{{Apple Inc.}}

{{Authority control}}

Category:2007 software

Category:Apple Inc.

Category:Apple Inc. operating systems

Category:Apple Inc. software

Category:ARM operating systems

Category:Computing platforms

Category:Mach (kernel)

Category:Mobile operating systems

Category:Products introduced in 2007

Category:Smartphone operating systems

Category:Tablet operating systems