Windows Phone 7 was released in fall 2010 as a replacement for Windows Mobile. The OS gained popularity for its highly-accessible 'Tile' interface, which gives users a visually-pleasing way accessing their smartphone features.
The Windows Phone 7.5 Mango update gave the OS better social networking integration, multitasking and camera features. It also added support for internet sharing, video chat and the ever-important option of custom ringtones. Smaller subsequent updates include 7.6 Tango and 7.8, which will make the Start screen more customisable a la Windows Phone 8.