Ive tried quite a number of mobile, iPhone/iPad chess programs and I found this one be the best by far! Im using it less to play against it (yes, I lost a few games, it even rates your play) but more for analyses of games I played with other people. It has plenty of useful features, including an option of sending/receiving pgn games. It is great also for quickly setting a position, like Mate-in-2,3 etc, end-game studies and puzzles.
Lastly, theres not a better tool for handling your correspondence games, if you happen to be into
correspondence chess. App support is also very responsive and helpful.
All in all, Im giving it 5-star mark without any hesitation.
grisha66 about Chess - tChess Pro, v1.8.0