Windows Mobile 6.1

Windows Mobile 6.1 is a minor upgrade to the Windows Mobile 6 platform that was released by Microsoft on April 1, 2008. Mainstream support for 6.1 ended on January 8, 2013.

Updated features
Windows Mobile 6.1 featured various performance enhancements and a redesigned Home screen featuring horizontal tiles that expand on clicking to display more information, although this new home screen is featured only on Windows Mobile Standard edition. This was not supported in the Professional edition.

Operating System
Aside from the visual and feature distinctions, the underlying CE versions can be used to differentiate WM6.0 from WM 6.1. The version of Windows CE in WM 6.0 is 5.2.*, with the final number being a 4 digit build ID (e.g. 5.2.1622 on HTC Wing). In WM 6.1, the CE version is 5.2.* with a 5 digit build number (e.g. 5.2.19216 on Palm Treo 800w).