Exchangeable Image File Format - Geolocation

Geolocation

The Exif format has standard tags for location information. As of 2012 a few cameras and a growing number of mobile phones have a built-in GPS receiver that stores the location information in the Exif header when a picture is taken. Some other cameras have a separate GPS receiver that fits into the flash connector or hot shoe. Recorded GPS data can also be added to any digital photograph on a computer, either by correlating the time stamps of the photographs with a GPS record from a hand-held GPS receiver or manually by using a map or mapping software. The process of adding geographic information to a photograph is known as geocoding. Photo-sharing communities like Panoramio, locr or Flickr equally allow their users to upload geocoded pictures or to add geolocation information online.

Most of Nokia's Nseries mobile phones (such as the N95) have a GPS receiver and use Location Tagger, a piece of software from Nokia Beta Labs. All captured images are tagged with corresponding GPS coordinates when a GPS signal is available. The second generation of iPhone (known as the iPhone 3G) by Apple Inc. is also equipped with a GPS receiver and uses the receiver to geotag photographs taken with the device. Subsequent generations (the iPhone 3GS, 4 & 4S) also support this feature. The first generation iPhone is not equipped with GPS, and uses a service provided by Skyhook to triangulate and approximate the location at which a picture was taken - using nearby cellular-phone towers and WiFi hot-spot signal-strength data. The Skyhook service provides approximate GPS location information which is then added to the Exif data associated with the picture. Also mobile phones with the Android operating system as well as BlackBerry smartphones with a camera and built-in GPS or Bluetooth GPS add-ons can geotag images with the included camera application.