1. Learn the hands
See how hands are matched: the colors work like a card: the same color means the same suit. X means you may call tiles and expose sets; C means concealed. Tap a hand to see a random winning example right below it.
2. Practice on your own
Build any hand you like. Players hold 13 tiles; the 14th tile (your last pick, or a called discard) completes Mahjong. Tap tiles below to add them. Drag a rack tile to move it, or tap it to select it and remove it.
Play with the tiles you're dealt. You get 13 random tiles. Draw a tile from the wall, then discard one, until you make Mahjong or the wall runs out. Choose how many draws you get: 25 is about what one player gets at a real four-player table. You can change it at any time. Drag tiles to rearrange them; tap a tile to select it for discarding.