Ian Ratcliffe helps out puzzle fans the world over with MobliSuDoKu for UIQ devices. Featuring 50 built in puzzles, and a SuDoKu Solver algorythm for problems found on the internet, it's a good first SuDoKu application for the platform. Let's hope he continues to develop it (and if you want to know more about SuDoKu, head over to Wikipedia).
SuDoKu Collection Available for UIQ
If you really want to know more about sudoku, and if you want a tutorial and free games, go to http://www.sudokushack.org