While both marker based and markerless AR technologies focus around the camera as the most important sensor, geo-location based AR focuses on the positioning sensors of the device such as the GPS, accelerometer, compass and gyroscope.
By locating the position of the user relative to the real world, digital information can be overlaid to provide information on the users current location and
surroundings. One of the biggest commercial implementations of geo-location
based AR has been done by the Dutch company Layar with their Layar Reality
Browser, a mobile application that has seen over 10 million installs