SmartGo Kifu is the best Go related app available for the IPad. If you play go and own an IPad, you should probably purchase this app. I have spent hundreds of hours using it, since it makes most every aspect of go study easier. The price is a bit higher than the average app, but you get what you pay for: something that is well designed, offering a lot without being cluttered, by a developer who is customer friendly, open to input and who releases updates that significantly improve the app, as opposed to just bug fixes. This is the sort of program that can be the difference between sustained interest and improvement in go and, well, frustration and disappointment. That said, it is much more an application for studying, and not for playing go, either online (you cannot play online through SmartGo) or against a computer (it offers an AI that is competitive on small boards, but not at 19 x 19) However that isnt such a big deal, since the strength of SmartGo Kifu is in its collection of pro games and problems (huge) and in its presentation of sgf files (totally brilliant). In particular, the book view option for viewing sgf files is without a doubt the best means available for viewing commented games. Imagine a go book with board diagrams that you can watch being played out and subtle visual distinctions to mark the difference between possible variations and the development of the game itself. This means that you dont fall unwillingly into one those click trances where you just passively take in the game (although, should one want to just relax and watch, theres an option to have it automatically proceed at a rate set by the user). How book view manages to reformat GTL reviews is pretty remarkable, and it makes them a lot easier to follow. In short, I use SmartGo Kifu to read Go Teaching Ladder game reviews, study games I played through various go servers (SmartGo can open sgf files from Safari), play through pro games in its collection either in the program itself or on my own board, and save information from Go books (joseki, fuseki, etc.) for easy reference later. This is the sort of stuff I would be doing anyway, but this app makes all of that a lot easier, and, to boot, lets me log in some time studying when Im sitting on the bus or waiting around.