A-GPS and GPS: An A-GPS is a standard GPS which can use the mobile network to
determine your location faster then a standard GPS. The A-GPS uses
mobile data to download information about satellites to improve the time
it takes to get a fix. To download this information the phone needs to
send certain data (for example CELL ID or WiFi info) about your location
over the internet which is the reason you get a question about
anonymous data when enabling the GPS. No personal data is sent.
If you have no data connection the GPS still works but it will take longer to get a fix.