DSChess is a homebrew chess game for the Nintendo DS. It builds upon a very strong open source chess engine called Fruit 2.1 by Fabien Letouzey (free again: www.fruitchess.com). The engine was changed to meet the requirements of the Nintendo DS. It is the strongest playing chess game on the Nintendo DS as two representative matches against Chessmaster and Schach has shown.

Changes:

Human vs. Human playing mode
Moves record in standard algebraic notation (use Select to switch)
Infinite thinking time for analyzing positions
Optimized memory management and hash tables increases AI search speed by more than 50%, so this version plays a lot stronger than the previous ones
Eleven playing levels with increasing play strength for beginners (under CPU-Settings/Levels)
Loads of bugs fixed

Release thread and discussion: http://forum.gbadev.org/viewtopic.php?t=15257

http://www.vonloesch.de/dschess