How to play
On the main screen choose the game you want to practice and hit the play button.
Then, a state or capital will start to move towards one of the players. When it passes the guide-line, answer buttons will appear. Tap the correct one to hit the problem back to the other player.
If you want to pause, use the pause button in the center. Once paused, the game can be resumed with the play button, or reset.
You get a point every time your opponent misses. The game is over when one player reaches seven points.