Gomoku

Against a virtual opponent, play by placing alternatively stones on any empty cell. The winner is the first player to form an unbroken chain of five stones horizontally, vertically, or diagonally.

The difficulty will automatically adjust the more you play.
12 levels of difficulty are available.

Gomoku uses a 12x16 grid best adapted for modern phones, instead of the traditional 15x15 or 19x19 boards.