A type of handset-based position location technology. To determine location, the phone takes readings from both GPS satellites and nearby cellular base stations (towers), with the help of a location server on the network.
The location server on the network is required to tell the phone which satellites to look for, and also to perform the complex calculations that provide precise location information.
This technology generally provides better accuracy than GPS-only and network-based technologies. A-GPS also works in places where GPS-only technologies do not work well, such as dense urban areas, inside buildings, and in moving cars.