Can I use the Windows Mobile 6 SDK to create applications that run on WM 5 & 6 devices?
• Yes, however there may be incompatibilities in cases where WM 5 applications use undocumented or unsupported APIs. See the What’s New for Developers in Windows Mobile 6 article on MSDN. • Note: Microsoft does not recommend using the WM 6 SDK to develop applications for WM 5 devices because there are new features requiring WM 6 based devices.