One of the reasons there are so many Windows Mobile devices is because the platform supports many different screen resolutions. Screen resolution is defined by the number of pixels down and across.

Many of these resolutions are quite common, such as 240×320 (QVGA) and 480×640 (VGA), but there are some interesting ones that we have yet to see, such as 440×240 and 400×240 for non-touchscreen, and 480×480 for touchscreen.