https://i.kinja-img.com/gawker-media/image/upload/s–uDoNH6Mv–/c_scale,fl_progressive,q_80,w_800/utowsidnmcflj77z8odd.gifOK so the app helps you draw like a CNC a picture on a wall with a can of spraypaint. There goes the graffiti artist industry.
http://gizmodo.com/this-simple-smartphone-app-may-just-trick-people-into-t-1795229911