Geometry Waves is an arcade/shooter game. You start as a triangle and you can progress to a circle. Shots are fired from the sides of your shape.
Rotate your shape and if you destroy the approaching shapes you get points, but if they hit you, your shape gets lowered a level down and you change color.
Every color has a power:
Yellow - shield
Green - rapid shots
Blue - freeze
Purple - rotation speed
Get as many points as you can.