My phone is a Windows Mobile 5 device, and comes with Windows Media Player. It plays wma files, and select mp3 files, but that’s about it. Since I have a LOT of mpg video, I went hunting for a real video player. PocketTV came out on top in my Google search.
This is probably the highest quality WM5 software I’ve found, far better than anything from Microsoft I’ve seen. When you install stuff, it asks if you want to install on the device, or on your memory chip. Anything from Microsoft will say (main memory highly recommeded). When you choose Main Memory, it always says "You choose "", main memory is recommended, would you like to continue?".
PocketTV got it right. It doesn’t care where you install it, and recognizes the choice you make.
It’ll let you browse your memory chip (Microsoft products do not) to find video, and plays it flawlessly, no stuttering, full screen, rotated any direction you’d like, etc. Pretty much any feature I could think of is available *except* no-loop. When it gets to the end of a video, it just starts playing it again.
PocketTV will work on pretty much any version of portable windows, going back to WINCE. I highly recommend it.
Oh, and it’s free for personal use.