VRmazing lets you draw your game on a piece of paper and have this paper scanned by a smartphone. Next you can do one of these two things :

  1. Goto an area big enough to walk freely in and enjoy total freedom whilst being immersed inside your 3D game.
  2. Put your phone inside a cardboard device to explore your real 3D world. You can navigate through your 3D game with a technique called ‘walking in place’

 

More info : vrmazing.eu