To mark a line, touch between the dots. To win, the line has to reach the other side.
You can play against the machine or against a friend. We recommend that you play against a friend, as it is a challenging game. Also, as it is compatible with Apple Watch, you will always carry it and you will not have an excuse to play a game.
The AI to play against the machine for now is easy, but enough to design your strategies to play against a friend. But in future updates we will continue to improve to make AI more complex.