Gomoku Go - Gobang, Connect 5/4 or Five in a Row(Phone) app for iPhone and iPad
Gomoku is an abstract strategy board game. Also called Gobang or Five in a Row, it is traditionally played with Go pieces (black and white stones) on a go board with 19x19 (15x15) intersections. however, because once placed, pieces are not moved or removed from the board.
Black plays first if white did not just win, and players alternate in placing a stone of their color on an empty intersection. The winner is the first player to get an unbroken row of five stones horizontally, vertically, or diagonally.