Windows Phone 7

Windows Phone 7 is the first version of Windows Phone released. The first version was released worldwide on October 21, 2010, and in the United States on November 8, 2010. The first major update, Windows Phone 7.5, began rolling out on September 27, 2011. It includes a mobile version of Internet Explorer 9, multitasking, Twitter integration, and SkyDrive (now OneDrive) support. Internally, the OS version received a bump to version 7.10. Windows Phone 7 devices could not update to Windows Phone 8 due to the switch to the NT Kernel. The final major update, Windows Phone 7.8, began rolling out on January 2010. It back ported several Windows Phone 8 features, including the improved Start screen, additional theme colors, and the ability for the lock screen to show the Bing homepage picture. Support for Windows Phone 7 ended on October 14, 2014.