KEEP MOVING forward until you hit a barrier. Then choose to turn left or right. Lock automatic rotation on your phone/tablet, hold it horizontally, and tilt it up/down/left/right. Face Sensing tracks your face to gauge tilting. Experimental Face Sensing controls added by @kriblo. Everything else by @colinmacc. Ok, so it might not be perfect... but it works better if you don't place your thumb over the camera lens on your phone ;)
