Half a zillion idea: use sound echolocation principles. Edit: http://www.gsmnation.com/blog/2013/06/19/echolocation-app-lets-you-map-rooms-like-a-bat/ http://w

Half a zillion idea: use sound echolocation principles. Edit: http://www.gsmnation.com/blog/2013/06/19/echolocation-app-lets-you-map-rooms-like-a-bat/ http://www.gsmnation.com/blog/2013/06/19/echolocation-app-le...