XO Duel

Gomoku 15×15

Goal: be the first to get 5 of your marks in a row – horizontally, vertically or diagonally.

How to play: the board is a 15×15 squared sheet. You take turns drawing your mark (X or O) in any empty square. Longer lines (6 or more) win too.

Draw: the whole board is full and nobody has 5 in a row.

Tip: stop your opponent's open three or four in time, and try to build two threats at once.

Tic Tac Toe 3×3

Goal: get 3 of your marks in a row – horizontally, vertically or diagonally.

How to play: the board has 3×3 squares. You take turns drawing X or O in an empty square.

Draw: all 9 squares are full and nobody has 3 in a row. With perfect play the game always ends in a draw.

4 in a row

Goal: line up 4 of your discs in a row – horizontally, vertically or diagonally.

How to play: the board stands upright and has 7 columns and 6 rows (42 places). You take turns dropping a disc (red or yellow) into any column from the top. It falls to the lowest free place of that column.

Blocking: don't only build your own four, stop your opponent's too.

Winner: the first to get 4 discs in a row. Draw: all 42 places are full and nobody has four.

Playing online

Create a game and send the code to a friend, or join with a code you received. Choose the pace: live – 30 seconds per move and you both play at once; or over distance – 3 days per move and you get a notification when it is your turn.

The winner can send the loser a funny animation. Trophies and statistics are kept on the server; the backup code gives them back after reinstalling the app.