R/G/B at Mac App Store analyse

R/G/B is a deceptively simple stacking game with a repeating sequence of red, green, and blue shapes. Upon each tap of the screen, a new red, blue, or green shape is created.  The shapes collect at the bottom of your screen, slowing filling your iPhone until you reach the top—level complete! The challenge is to avoid contact between any two shapes of the same color. If this happens, the same-colored balls will explode, with the surrounding shapes collapsing to fill the void left in the explosions wake.