Geometry Dash is a 2D platformer where you control a square that has to get to the end of different levels, avoiding the tons of different obstacles it encounters along the way.
Your square hero always moves forward, so your only task is to make it jump at the correct time in order to avoid the different obstacles. Of course, those jumps usually have to be calculated down to the millimeter or you'll hit something and you'll have to start the level all over again from the beginning.
This free version of Geometry Dash only offers a fraction of the levels available in the paid version, but there are more than enough to give you an idea of what awaits you: a challenge where your skills and reflexes will be key if you want to come out winning.
Geometry Dash is a platformer with very simple mechanics that nevertheless is able to present an extremely difficult challenge. And the best thing about it is that it is able to do so in a very fun way, constantly showing you that it's your fault if you fail.