Originally Posted by murraypaul
You are wrong.
An aGPS system has two separate functions.
The first is a traditional GPS satellite system, that works that same as other GPS systems.
The second is a cell-tower based system, which is used when GPS lock has not been achieved.
It is true that cellphones generally have smaller, poorer, antenna than dedicated GPS units, but that has nothing to do with the aGPS function, it is a hardware difference.
These devices can be used as GPS units with no SIM cards installed, so no cell connection.
Assisted GPS can also mean that you download data from the net to help get the first fix.