Checking costs 30 points each time. Revealing costs 100 per letter and ends a clean solve.
Tap a square, then type. Tap the same square again to switch between across and down. The clue bar shows what you are solving; its arrows move to the next clue.
The grid is complete when every square is right. Wrong letters are only marked if you check them, or turn on autocheck.
Keyboard: arrows move, Tab jumps to the next clue, Backspace clears.