This is a real training for Super Hexagon game (try out this game and buy Super Hexagon later on if you like the game concept).
With the same concept, all you have to do is moving the triangle clock wise or counter clock wise to avoid the arc lines crashing in to the center by touching right or left side of the screen. If you can hold on for more than 45 second, you will unlock the next speed.
Warning: this game concept is not recommended for people with motion sickness.