Windows Phone 7.8

This page provides details for the version history of the Microsoft's Windows Phone branded mobile operating systems, from the release of Windows Phone 7 in October 2010, which was preceded by Windows Mobile version 6.x.

Windows Phone 7 was the first release of the Windows Phone mobile client operating system, released worldwide on October 21, 2010, and in the United States on November 8, 2010.

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7.0.7004

7.0.7008

7.0.7390 (NoDo)

7.0.7392

7.0.7403

At the 2011 Mobile World Congress, Steve Ballmer announced a major update to Windows Phone 7 due toward the end of the year, Windows Phone 7.5, codenamed Mango. The new OS would address many of the platform's shortcomings, including a mobile version of Internet Explorer 9 that supports the same web standards and graphical capability as the desktop version, multi-tasking of third-party apps, Twitter integration for the People Hub, and Windows Live SkyDrive access. Although the OS internally identifies itself as version 7.1, it is marketed as version 7.5 in all published materials intended for end-users.

Microsoft started rolling out Windows Phone 7.5 to both the United States and International markets on September 27, 2011. The first phones that came pre-loaded with Windows Phone 7.5 were released in the last quarter of 2011.

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