A winning hand is 14 tiles: four sets plus one pair. A set is three in a row of one suit, three identical tiles, or four identical tiles (a kong, which gets you one extra tile).
Three suits numbered 1 to 9, plus honours. Flowers don’t go in sets: put them face up in front of you and draw a replacement. They’re worth bonus points when you win.
Group by suit, then by number, with honours at the end. Sets and almost-sets jump out, and you’ll see which tile you’re waiting for.
One tile is picked as the joker at the start of every round and shown at the top of the screen. All four copies of it stand in for any tile. Each joker in your winning hand is +1, a hand with no joker at all gets +2, and holding all four is an instant win.
The dealer is East. Going counter-clockwise: South, West, North. Your wind is your seat number for flowers (East 1, South 2, West 3, North 4), and a triplet of your wind is worth a point.
On your turn, draw a tile and discard one. Anyone can take a discard to make a triplet (Pong), a kong, or to win. Only the player right after the discarder can take it for a sequence (Chow), so you can only Chow from the player on your left. Hu beats Pong, and Pong beats Chow.
You need at least 3 points to win. Calling Hu under 3 points is Hu Palsu: you pay 30 and everyone else gets 10. Use Check my hand to see your points first.
Tap I won, enter your tiles and how you won, and send it to the game master. The app does the scoring and the game master approves it.