Windows Mobile

Windows Mobile was based on the Windows CE kernel and first appeared as the Pocket PC 2000 operating system. Throughout its lifespan, the operating system was available in both touchscreen and non-touchscreen formats. It was supplied with a suite of applications developed with the Microsoft Windows API and was designed to have features and appearance somewhat similar to desktop versions of Windows. Third parties could develop software for Windows Mobile with no restrictions imposed by Microsoft. Software applications were eventually purchasable from Windows Marketplace for Mobile during the service's brief lifespan.

Most early touchscreen devices came with a stylus, which could be used to enter commands by tapping it on the screen. The primary touch input technology behind most devices were resistive touchscreens that often responded more accurately to a stylus for input, but could also be driven by a finger. Later devices used capacitive touchscreens, which were more suited to finger input. Along with touchscreens a large variety of form factors existed for the platform from the humble 'candy bar' style to sliding, folding and articulating keyboards.

A key software feature of Windows Mobile was ActiveSync; a data synchronization technology and protocol developed by Microsoft, originally released in 1996. This allowed servers running Microsoft Exchange Server, or other third party variants (such a Google Mail), to act as a personal information manager and share information such as email, calendar appointments, contacts or internet favorites.

Despite being replaced by Windows Phone, Windows Mobile is still in use to this day in the enterprise market by supermarket chains and courier companies.