The app, step by step. The rules are on their own page; this is what you'll see and what to tap.
Tiles the others laid since you last looked glow gold for a moment, and the line over the table says who laid what.
Tap a tile on your rack to lift it, then tap + new set or a set you've started. The count says how far you are — "18 of 30". Done wakes up at 30.
Once you've opened, tap any tile on the table to lift it and tap the set it should go to. Every set you touch gets a gold edge. Just leave every set whole.
A set that isn't a run or a group gets a red edge and the app says which one. Done stays dim until it's fixed. Undo puts everything back to the start of your go — no clock, no penalty.
Hold the tile a ★ stands for? Lift it and tap the ★. The ★ comes to you lifted — put it into a set this go.
Done sends your whole go at once. When someone empties their rack the results come up: minus what's left on each rack, the winner takes the total. Rematch deals the same table again.