Chess apps

Could you clarify specifically what you're looking for?

I have an iphone 3gs with shredder on it and love it. You can setup the board as you like, run an analysis of the positions and play the recommended move or play what you'd like. You can step through all the moves of the current game(it does NOT keep a history of games) to see where the mistakes were. It's the highest rated chess app on itunes. They have a free (lite) version too.

There are some inexpensive ones for like pocket pcs such as chess endings chess middlegames chess tactics that are really nice and very inexpensive. Don't know how they'd work on an ipad

Made a mistake True, I just figured out that you can save games and analysis to iphone with shredder app. You can also email them too.