Paper POP.

1. Pick a letter. Either player can place P or O in any empty square. Letters stay where you put them.
2. Make a POP. Three consecutive letters spelling POP horizontally, vertically or diagonally earn one point. Each new POP counts, including overlapping ones.
3. Keep your turn. Score at least one point and play again. Otherwise, your opponent goes next.
4. Fill the paper. The higher score wins when the board is full. Equal scores are a draw. The starting player alternates each round.

Choose a 6×6, 7×7, 8×8, 9×9 or 10×10 grid. Larger boards scroll horizontally on small screens so every square remains easy to tap. Computer matches and private friend rooms need an internet connection. In online play, each turn has a one-minute limit; running out of time or resigning awards the round to your opponent. Rooms expire after three hours.