Network-based real time registered augmented reality for mobile devices

A method of operating a mobile device with a camera, a display and a position sensor to provide a display of supplementary information aligned with a view of a scene. One or more image obtained from the camera is uploaded to a remote server together with corresponding data from the position sensor. Image processing is then performed to track image motion between that image and subsequent images obtained from the camera, determining a mapping between the uploaded image and a current image. Data is then received via the network indicative of a pixel location for display of supplementary information within the reference image. The mapping is used to determine a corresponding pixel location for display of the supplementary information within the current image, and the supplementary information is displayed on the display correctly aligned with the view of the scene.