Before you begin redecorating the living room, bedroom, or office, it’s always a good idea to start off with an exact measurement of a room’s dimensions—easy enough in an empty, small room, but stretching out a tape measure or across a furnished room? Challenging, if not an acrobatic feat. RoomScan simplifies the process, creating a surprisingly accurate floorpan of any room using your iPhone’s wi-fi, GPS and gyroscope to determine the distance across walls.