I think
PocketGrandmaster is still one of the strongest Pocket PC chess machines around. It was the champion before and had also won a few awards for Pocket PC game category. It's very strong, has timer function, save function, view games, download games to view, customisable constraints (limit machine's thinking depth or time limit on game or per move), etc. However, one thinkg I wished it had was playing levels from easy to hard. Most of the time, the machine is really a tough nut to crack unless u limit its thinking depth (number/depth of moves it can calculate up to). BTW, you can even connect your device to an electronic chessboard and PocketGrandmaster can inegrate quite well.