Maps displays your location on the map using GPS, A-GPS, Wi-Fi, or network (cell ID) based positioning.
The global positioning system (GPS) is a satellite-based navigation system used for calculating your location. Assisted GPS (A-GPS) is a network service that assists your GPS receiver, improving the speed and accuracy of the positioning. In addition, other enhancements to GPS may be used to improve and speed up the positioning. These may require transferring small amounts of data over the cellular network.
Wi-Fi positioning improves position accuracy when GPS signals are not available, especially when you are indoors or between tall buildings.
With network (cell ID) based positioning, the position is determined through the cellular system your phone is currently connected to.
To save on data costs, you can deactivate A-GPS, Wi-Fi, and network (cell ID) based positioning in your phone positioning settings, but calculating your location may take much longer, the location can be more inaccurate, and the GPS receiver can lose location more frequently.
The availability and quality of GPS signals may be affected by your location, satellite positions, buildings, natural obstacles, weather conditions, and adjustments to GPS satellites made by the United States government. GPS signals may not be available inside buildings or underground.
Do not use GPS for precise location measurement, and never rely solely on the location information provided by GPS and cellular networks.
The trip meter may not be accurate, depending on the availability and quality of your GPS connection.
Depending on the available positioning methods, the accuracy of positioning may vary from a few yards to several miles.