If you already know the rules of 4-player Mahjong, this app is good for practice. The app appears to use 136-tile Chinese rules. The app is fully functional, but it could use some polish (e.g., animations, explanation of the tutor-recommended move).
Aleche36,
The real deal!
This is the Majong they play in China, not the tile matching game that has flooded the app store. I is fun and challenging.