You tap the screen. A tiny square cube launches itself into the air, arcs over a triangular spike, and lands cleanly on the other side. For about three seconds, you feel like a genius. Then the music speeds up, three spikes appear in quick succession, and your little cube explodes into a shower of pixels. Welcome to Geometry Dash — a game where one mistake sends you all the way back to the beginning, and somehow you don't mind one bit.