ChessGenius, award winning chess program. The author's chess programs have won ten World Championships.
-Full take back and forward
-Big opening book and named openings
-Set up position
-33 playing levels
-Display of thinking
Lite version restricts the use of some...
Chess Genius Lite — I like this app because it shows you all of the possible moves a piece can make when you tap it and it also keeps track of all of the previous moves. Very Educational.