A must have

It seems expensive, but actually it is a steal. It would cost you so much more to buy problems books separately to reach the same number you have in the app. After, you have the annotated games that would also cost a lot if you were to buy the book version of them. If you are even a little bit serious about Go, you must invest in this app.

Miroa06 about SmartGo Kifu, v4.2