XAP (file format)

{{Short description|Microsoft file format with multiple uses}}

{{Infobox file format

| name = XAP

| icon =

| extension = .xap

| mime = application/x-silverlight-app

| type code =

| uniform type =

| owner =

| genre = Package management system, file archive

| container for = Software package

| contained by =

| extended from = ZIP

| extended to = APPX

| standard =

}}

XAP is the file format used to distribute and install application software and middleware onto Microsoft's Windows Phone 7/8/8.1/10 operating system, and is the file format for Silverlight applications. Beginning with Windows Phone 8.1, XAP was replaced by APPX as the file format used to install WinRT apps on the Windows Phone platform, a move which was done by Microsoft in order to unify the app development platforms for Windows Store apps and Windows Phone apps.{{cite web | url=https://www.theverge.com/2014/2/11/5400660/windows-phone-8-1-features-leaked | title=Windows Phone 8.1 includes universal apps and lots of feature updates | date=11 February 2014 }}

XAP files are ZIP file formatted packages, however Microsoft has enabled XAP file encryption, meaning the file can no longer be opened with a standard ZIP extractor. The MIME type associated with XAP files is application/x-silverlight-app.{{cite web|url=http://www.file-extensions.org/xap-file-extension |title=File Extension .XAP Details |publisher=File-Extensions.org |access-date=2015-06-16}}

The Windows Phone Marketplace allows users to download XAP files to an SD card and install them manually.{{cite web|url=http://www.windowsphone.com/en-gb/How-to/wp8/apps/how-do-i-install-apps-from-an-sd-card |title=How do I install apps from an SD card? | Windows Phone How-to (United Kingdom) |publisher=Windowsphone.com |access-date=2014-02-10}}

XAP is also the extension for XACT Audio Projects, openable with the Microsoft Cross-Platform Audio Creation Tool.

Silverlight XAP Files are not openable with the Audio Creation Tool, and XACT XAP files are not archives.