Global Positioning System (GPS)

A satellite navigation system that provides 24 hour 3-D position, velocity and time information to suitably equipped users anywhere on or near the surface of the Earth.

There are more than two dozen GPS satellites above the earth in six orbital planes, which broadcast precise timing signals by radio to GPS receivers, allowing them to accurately determine a phone's location (latitude, longitude and altitude) in any weather, night or day. A GPS phone can be used to pinpoint a precise location or to help navigate.