Windows Mobile is Microsoft's attempt to convert the most successfull desktop environment to fit on a mobile device. The user interface is somewhat similar to the desktop version but the similarities does not end here. The API is large, well documented and similar to Win32 allowing the developer a lot of elbow-room.
Project Mobile Devices currently has one developer dedicated to exploring the potential of this platform. It is the hope that Windows Mobile lacks som of the shortcommings of Symbian so that an application unrealisable on Symbian could be possible on Windows Mobile and vice versa.