Most mobile devices that are currently on the market offer the ability to give the user their physical location. This can be provided from a number of sources (such a cell triangulation) but its most commonly generated from Global Positioning Satellite (GPS) client devices that are now built into the mobile devices themselves.
A location based service is one in which utilise the location awareness property to enrich a service. Location based services can be used to provide information to the device user about their surrounding and also allow businesses to keep track of where and what mobile devices are. A key examples of where this is already being utilised is the Haulage industry. Drivers can be given up to date instructions on where deliveries should be taking place and management always know where their drivers are.