From the Motorola Website:
How does my phone use GPS & AGPS?
Your mobile device can use Global Positioning System (GPS) signals for location-based applications. GPS uses satellites controlled by the U.S. government that are subject to changes implemented in accordance with the Department of Defense policy and the Federal Radio Navigation Plan. These changes may affect the performance of location technology on your mobile device.
Your mobile device can also use Assisted Global Positioning System (AGPS), which obtains information from the cellular network to improve GPS performance. AGPS uses your wireless service provider's network and therefore airtime, data charges, and/or additional charges may apply in accordance with your service plan. Contact your wireless service provider for details.
Location-based information includes information that can be used to determine the approximate location of a mobile device. Mobile phones which are connected to a wireless network transmit location-based information. Devices enabled with GPS or AGPS technology also transmit location-based information. Additionally, if you use applications that require location-based information (e.g. driving directions) such applications transmit location-based information. This location-based information may be shared with third parties, including your wireless service provider, applications providers, Motorola, and other third parties providing services.
When you make an emergency call, the cellular network may activate the AGPS technology in your mobile device to tell the emergency responders your approximate location.
AGPS has limitations and might not work in your area. Therefore:
* Always tell the emergency responder your location to the best of your ability; and
* Remain on the phone for as long as the emergency responder instructs you.
* Go outside and away from underground locations, covered vehicles, structures with metal or concrete roofs, tall buildings, and foliage. Indoor performance might improve if you move closer to windows, but some window sun shielding films can block satellite signals.
* Move away from radios, entertainment equipment, and other electronic devices.