Is the Pocket PC OS the same as Windows CE?
No. The Pocket PC OS is a custom version of Windows CE developed by Microsoft. It contains APIs and applications that are not included in Windows CE 3.0 itself. Likewise, Windows CE contains components that are not included in the Pocket PC OS. Pocket PC devices do not all use the same Pocket PC OS, either. OEMs who build these devices make custom versions of the Pocket PC OS to add features specific to their devices. Thus, a Pocket PC device from one OEM might include different applications or device drivers than a Pocket PC from another OEM.