Sometimes it's the simplest games that are the most fun. How about playing tennis with yourself? All you need to do is concentrate and make sure that the ball remains in the air. Try it out.
Tap the paddle to start game; drag paddle to keep it under the ball. If you lose control of the ball, the game ends.
Avoid large movements; small shifts of the paddle will keep the ball in the air longer. Play often to increase your personal best and compete on the leaderboard!