Originally Posted by tompe
The gps in the phone is a real gps. So I do not understand what you mean. A car gps usually have a better antenna then the one in the phone but that is another thing. And with a phone you can use data from the net to get the initial fix. And I compared Google navigation to a Garmin and did not see any quality differences in the routing.
I don't doubt that some phones have a complete GPS chip and system, but many have "aGPS" which is "assisted GPS" which works off the location of cell towers. There can be errors tied to where you are in relation to the towers and how far away the towers are.
There are also various levels of GPS chips with variations on sensitivity and number of satellites used.