aGPS as deployed by the CDMA providers is just as much a "real" GPS system as any other; it also has the additional capability to use cell-tower triangulation in areas where GPS signal is inaccessible or inaccurate, or to refine a gross satellite fix.

Most cellphones don't have the computing power onboard to get a first-fix in a reasonable amount of time, so they do offload some of the computations to the network in most cases. This also allows them to "jumpstart" the first fix by providing a GPS ephemeris to the mobile via the mobile data network rather than the 50 bps downlink from the GPS satellite.

Now, it happens that some carriers have restricted access to the GPS APIs on some of their phones - compare, say, the Sprint 8130 and the VZW 8130 in GPS capabilities with respect to Google Maps. But it's the same underlying hardware, and the CDMA implementation of aGPS is just that - Assisted GPS...

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