jjnz1:Kilack:kiwijunglist: Yes GPS + cellular network tower info = aGPS.
but what was strange is GPS on my phone could not work at all with EDGE/3G disabled.
That is nasty... it shouldn't be like that. Obviously an issue if you are somwhere with no coverage.
Hi Kilack, most phones are AGPS and dont really work that well without cell reception. Including the iphone.
The GPS chips in them are different to devices like Garmin. Its a shame really.
Well in some early agps phones there were limitations that they couldn't function with true/pure GPS.
That should definitely not be the case with the iphone 3gs, iphone 4 or the galaxy s and probably every other decent phone out there.
The galaxy s has a broadcom 4751 chip, a step up from the 4750, iphone 3gs has a broadcom 4750.
These chips can definitely function _very_ well with only GPS. The assisted mode defiitely will help you get a lock in seconds instead of minutes but won't help with accuracy which is purely down to the GPS once it kicks in and using the satellites,.
The new tomtom line, the XXL 550 dedicated GPS navigators also use the broadcom 4750 chips so the galaxy s's actually have a better gps chip in them than the tomtoms.
The only difference with a phone once its using the satellites is that there is probably a smaller antenna in the phone than a dedicated GPS unit but then again these gps chips are very sensitive...