dual SIM

The first phone to include dual SIM functionality was the Benefon Twin, released by Benefon in 2000.{{cite news |title=Benefon unveils handsets in grand media launch |url=https://www.philstar.com/business/business-as-usual/2001/12/24/144747/benefon-unveils-handsets-grand-media-launch |access-date=30 July 2019 |work=The Philippine Star |date=24 December 2001}} More dual SIM phones were introduced in about 2007, most of them coming from small Chinese firms producing phones using Mediatek systems-on-a-chip. They started to attract mainstream attention.{{cite web | last=Chase | first=Brendon | title=Shanzhai ji: All you need to know about fake phones | website=CNET | date=9 July 2009 | url=https://www.cnet.com/tech/mobile/shanzhai-ji-all-you-need-to-know-about-fake-phones/|url-status=live| archive-url=https://web.archive.org/web/20090714224027/http://www.cnet.com.au/shanzhai-ji-all-you-need-to-know-about-fake-phones-339297258.htm | archive-date=14 July 2009 }}{{cite web|url=https://www.gsmarena.com/dual_sim-review-154p2.php|title=Dual SIM review: Mobiles go two-in-one - page 2|date=3 August 2007|work=GSM Arena|access-date=27 April 2014}}

Such phones were initially eschewed by major manufacturers due to potential pressure from telecommunications companies,{{cite web|url=https://www.gsmarena.com/dual_sim-review-154.php|title=Dual SIM review: Mobiles go two-in-one|date=3 August 2007|work=GSM Arena|access-date=27 April 2014}} but from about 2010 Nokia, Samsung, Sony and several others followed suit, with the Nokia C2-00, Nokia C1-00 and Nokia C2-03 and most notably the Nokia X,{{cite web|url=https://www.talkandroid.com/197558-nokia-unveils-3-new-android-handsets-nokia-x-nokia-x-and-nokia-xl/|title=Nokia unveils 3 new Android handsets: Nokia X, Nokia X+, and Nokia XL|last=Nazarian|first=Robert|work=TalkAndroid.com|date=24 February 2014}}{{cite web|title=Dual SIM Nokia C2 revealed|url=http://conversations.nokia.com/2010/06/03/dual-sim-nokia-c2-revealed-photo-gallery/|publisher=Nokia Corporation|date=3 June 2010|archive-url=https://web.archive.org/web/20110714034500/http://conversations.nokia.com/2010/06/03/dual-sim-nokia-c2-revealed-photo-gallery|archive-date=14 July 2011|url-status=dead}}{{cite web|title=Nokia C1 unleashed with double-SIM functionality|url=http://conversations.nokia.com/2010/06/03/nokia-c1-unleashed-with-double-sim-functionality-photo-gallery/|publisher=Nokia Corporation|date=3 June 2010|author=Rhiain|archive-url=https://web.archive.org/web/20110714040320/http://conversations.nokia.com/2010/06/03/nokia-c1-unleashed-with-double-sim-functionality-photo-gallery|archive-date=14 July 2011|url-status=dead}} phones from Samsung's Duos series,{{cite web|url=http://culturemob.com/samsung-galaxy-duos-2-samsung-galaxy-core-specs-price-comparison|title=Samsung Galaxy S Duos 2 vs Samsung Galaxy Core – Specs and Price Comparison|work=CultureMob|access-date=27 April 2014|archive-url=https://web.archive.org/web/20140427211917/http://culturemob.com/samsung-galaxy-duos-2-samsung-galaxy-core-specs-price-comparison|archive-date=27 April 2014|url-status=dead}} and the Sony Xperia Z3 Dual, Sony Xperia C{{cite web|url=http://www.phonearena.com/reviews/Sony-Xperia-C-Review_id3524|title=Sony Xperia C Review|date=11 December 2013|work=Phone Arena|access-date=27 April 2014}} and tipo dual.{{cite web|url=http://www.phonearena.com/phones/Sony-Xperia-tipo-dual_id7152|title=Sony Xperia tipo dual specs|work=Phone Arena|access-date=27 April 2014}}{{cite web|url=https://www.esato.com/phones/Sony-Xperia+Tipo+Dual-932|title=Sony Xperia Tipo Dual specifications and reviews|work=Esato|access-date=27 April 2014}} Apple added dual SIM support in its 2018 iPhone XS models, with models sold in China containing two physical SIM slots, and models sold elsewhere supporting dual SIM by means of (Embedded) eSIM alongside a single physical SIM.{{Cite news|url=https://www.cnet.com/news/apple-brings-dual-sim-support-to-the-iphone/|title=Apple brings dual-SIM support to the iPhone XS and XS Max|date=2018-09-12|work=CNET|access-date=2018-11-09|language=en}}{{Cite news|url=https://www.zdnet.com/article/what-you-need-to-know-about-the-iphones-new-dual-sim-esim-feature/|title=What you need to know about the iPhone's new dual-sim feature|last=Cipriani|first=Jason|work=ZDNet|access-date=2018-11-09|language=en}}

For originating communications via the mobile phone network, the way to choose which SIM is used may vary on different phones. For example, one can be selected as primary or default for making calls, and one (which could be the same one) for data. Apple phones supporting dual SIMs can be set up to automatically use a specific SIM for each contact or the same one used for the last call to the contact, for iMessage, and for FaceTime.{{cite web | title=Using Dual SIM with two nano-SIM cards | website=Apple Support | date=18 January 2023 | url=https://support.apple.com/en-gb/HT209086}} Typically when dialling or sending a message an option to select a SIM is displayed.

Prior to the introduction of dual SIM phones, adapters that fit in the SIM card slot and hold two SIMs, with provision to switch between them when required.{{cite web|url=https://www.cellphonebeat.com/duo-sim-d2-converts-a-standard-mobile-phone-to-dual-sim-phone-in-minutes.html|title=Duo SIM D2 converts a standard mobile phone to dual SIM phone in minutes|work=CELLPHONEBEAT|access-date=27 April 2014}}

In dual SIM {{Em|switch}} phones, such as the Nokia C1-00, only one SIM, selected by the user, is active at any time; it is not possible to receive or make calls on the inactive SIM.{{cite web|url=https://www.gsmarena.com/nokia_c1_00-review-517.php|title=Nokia C1-00 review: Dual SIM-phony|work=GSM Arena|access-date=27 April 2014}}

Dual SIM Dual {{Em|Standby}} (DSDS) phones allow both SIMs to be accessed by using time multiplexing. When one SIM is in active use, for example on a call, the modem locks to it, leaving the other SIM unavailable. Older examples of dual-SIM standby phones include the Samsung Galaxy S Duos,{{cite web|url=https://androidcommunity.com/samsung-galaxy-s-duos-unveiled-with-dual-sim-capabilities-20120820/|title=Samsung GALAXY S DUOS unveiled with dual-SIM capabilities|date=20 August 2012|work=Android Community|access-date=27 April 2014}} the Sony Xperia M2 Dual,{{cite web|url=http://www.sonymobile.com/global-en/products/phones/xperia-m2-dual/|title=Xperia M2 Dual|date=27 July 2014|work=Sony|access-date=27 July 2014}} and the iPhone XS, XS Max and iPhone XR.{{cite web|url=https://techcrunch.com/2018/09/12/apple-introduces-the-iphone-xs/|title=Apple introduces the iPhone Xs and iPhone Xs Max news|work=TechCrunch|date=September 12, 2018|access-date=September 12, 2018}}

Dual SIM Dual {{Em|Active}} (DSDA) phones have two transceivers, and can receive calls on both SIM cards, at the cost of increased battery consumption and more complex hardware.{{cite web|url=https://www.gsmarena.com/glossary.php3?term=dual-sim|title=Dual-SIM - Mobile terms glossary|work=GSM Arena|access-date=27 April 2014}}{{cite web|url=http://gadgetstouse.com/gadget-tech/dual-sim-dual-standby-and-dual-sim-dual-active/8985|title=What is Dual SIM Dual Standby and Dual SIM Dual Active|work=Gadgets To Use|access-date=27 April 2014}} One example is the HTC Desire 600.{{cite web|url=http://www.phonearena.com/reviews/HTC-Desire-600-Review_id3386/page/2|title=HTC Desire 600 Review - Interface, Functionality, Dual SIM and Internet|date=9 August 2013|access-date=27 April 2014}}

File:Redmi 13 with Hybrid SIM slot taken out.png card in place of the second SIM slot.]]

Some telephones have a primary and a secondary SIM slot that support different generations of connectivity. For example, 4G and 3G primary, and 3G and 2G secondary,{{cite web |title=Redmi Note 4 Specification |url=https://www.mi.com/in/note4/specs/ |website=Xiaomi India |access-date=10 September 2018 |quote="When two SIM cards are used simultaneously, the primary SIM can support 4G+/ 4G / 3G / 2G calls and data while the secondary SIM can support 3G calls only."}} or 5G and 5G, or 5G and 4G.{{cite web | title=Dual SIM 5G phones: What's the deal with 5G+5G technology?|last=Simons|first=Hadlee | website=Android Authority | date=10 April 2021 | url=https://www.androidauthority.com/dual-sim-5g-phones-1136099/}} Selecting either of the SIMs as primary is usually possible without physically swapping the SIMs.

Some phone models utilize a "hybrid" SIM tray, which can hold either two SIM cards, or one SIM card and one MicroSD memory card.{{cite web|url=https://www.pcadvisor.co.uk/review/android-smartphones/umi-zero-octa-core-smartphone-review-3591690/|title=UMI Zero octa-core smartphone review - Review - PC Advisor|author=Marie Brewis|work=PC Advisor|access-date=30 November 2015}}{{cite web|url=http://www.phonearena.com/news/Rare-breeds-Dual-SIM-phones-with-separate-microSD-card-slot-no-hybrid-SIM-tray_id81795|title=Rare breeds: Dual SIM phones with separate microSD card slot (no hybrid SIM tray)|work=PhoneArena.com|access-date=30 August 2016}} The Huawei Mate 20 range introduced a proprietary memory card format called Nano Memory, exactly the size and shape of a nano SIM card.{{Cite web|url=https://www.theverge.com/circuitbreaker/2018/10/16/17985578/huawei-nano-memory-cards-nm-microsd-replacement-mate-20-pro|title=Huawei's Nano Memory Cards are replacing microSD on its latest phones|last=Gartenberg|first=Chaim|date=2018-10-16|website=The Verge|access-date=2019-02-13}}

Some devices accept dual SIMs of different form factors. The Xiaomi Redmi Note 4 has a hybrid dual SIM tray that accepts one micro SIM card and one nano SIM card, the latter of which can be swapped for a MicroSD card.

Dual SIM phones have become popular especially with business users{{cite web|url=http://blog.clove.co.uk/2013/12/14/htc-one-dual-sim/|title=HTC One Dual-SIM|date=14 December 2013|access-date=27 April 2014}} due to reduced costs by being able to use two different networks, with one possibly for personal use or based on signal strength or cost, without requiring several phones.

Some sub-contract Chinese companies supply inexpensive dual SIM handsets, mainly in Asian countries. The phones, which also usually include touch screen interfaces and other modern features, typically retail for a much lower price than branded models. While some such phones are sold under generic names or are rebadged by smaller companies under their own brand, numerous manufacturers, especially in China, produce phones, including dual SIM models, under counterfeit trademarks such as those of Nokia or Samsung,{{cite magazine|url=https://www.wired.co.uk/magazine/archive/2011/01/features/shanzai|title=Shanzai! (Wired UK)|magazine=Wired UK|access-date=5 August 2013}} either as cosmetically-identical clones of the originals, or in completely different designs, with the logo of a notable manufacturer present in order to take advantage of brand recognition or brand image.

Dual SIM phones are common in developing countries, especially in China, Southeast Asia and the Indian subcontinent, with local firms like Karbonn Mobiles, LYF, Micromax and Cherry Mobile releasing feature phones and smartphones incorporating multiple SIM slots.{{cite web|url=https://www.yugatech.com/mobile/cherry-mobiles-uber-cheap-dual-sim-phones/|title=Cherry Mobile's uber cheap dual SIM phones|date=9 June 2009|work=YugaTech|access-date=27 April 2014}}{{cite web|url=http://gadgets.ndtv.com/mobiles/news/karbonn-launches-four-budget-android-dual-sim-smartphones-under-rs-7500-432545|title=Karbonn launches four budget Android dual-SIM smartphones under Rs. 7,500|last=Pratap|first=Ketan|date=15 October 2013|work=NDTV|access-date=27 April 2014}}

The French Wiko Mobile is also an example of rebadged Chinese Dual-SIM phones sold in few European countries as well as in North-West Africa.

Dual SIM phones have been rare in countries where phones have been usually sold on contract, as the carriers selling those phones prevent SIMs from competing carriers from being used with the phones. However, dual SIMs have been popular in locations where people normally buy phones directly from manufacturers. In such places there is little lock-in to carrier networks, and the costs of having two phone numbers are much lower.

Dual SIM phones allow separate numbers for personal and business calls on the same handset. Access to multiple networks is useful for people living in places where a single network's coverage may prove inadequate or unreliable. They are also useful in places where lower prices apply to calls between clients of the same provider.{{cite web|url=https://onlupdates.blogspot.com/2017/09/operating-systems-used-by-hackers.html|title=Could Americans Learn to Love Dual-SIM Phones?|work=PCMAG|access-date=30 November 2015}}

Dual SIM phones allow users to keep separate contact lists on each SIM, and allow easier roaming by being able to access a foreign network while keeping the existing local card.{{cite web|title=8 reasons to opt for a Dual SIM phone|url=http://conversations.nokia.com/2011/09/12/8-reasons-to-opt-for-a-dual-sim-phone/|website=convre|access-date=25 July 2014}}

Vendors of foreign SIMs for travel often promote dual-SIM operation, with a home country and local SIM in the same handset.

{{Commons category}}

• Dual mode mobile
• Subscriber Identity Module
• SIM cloning
• Shanzhai

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{{Mobile phones}}

Category:Mobile phones

Category:Mobile telecommunications