Dune!

Dune - is a game in which you will test your sense of time. Basically, you gain control on a ball that has to fly above the drawn line. You use one finger to control the speed, the moment of the release and landing. Each of those aspects has to be perfect, because if you chose to release your finger too early or too late you won't gain the points or even you'll have to start from the beginning. But if you can manage to do it well, then you can expect a combo, which gives you additional points.

The game itself has a nice graphics and doesn't use any disturbing music or sounds, so you can launch your own playlist. It's a perfect time-killer for a bus ride or a short break.