Description: =============================== "one of the more striking budget games we've encountered..." - slidetoplay.com' "In one word, simply addictive." - iphonefootprint.com "...yet another interesting suggestion of how Apple’s touchscreens continue to inspire developers to come up with new gameplay ideas" - ilounge.com =============================== Petri. Simple to play. Impossible to master. The screen is filled with moving colors. Drag your finger to erase the color underneath. Double tap the screen to change the color to something else. Try to make the screen whatever color is at the bottom. You haven't seen anything quite like it.