I think some people are unclear about GPS and AGPS.

Practically all new Smartphone nowadays have built in or Integrated GPS receiver chip inside. Since the sky is a big big place, it will always take some time for it to find the location of the various satellite. Time taken can varies from few seconds to few minutes or forever......

To ASSIST the built-in GPS chip to locate the satellites faster, the phone will send a message to Telco seeking the approximate location of the satellites. The Telco will send that information in form of data (approximately 10KB or 10 sen worth) back to the phone. Armed with that data, the GPS chip can find the satellites a lot faster....mere few seconds. Since the Smartphone has requested ASSISTANCE from Telco, this is called Assisted GPS or A-GPS. Practically all Smartphone has this feature that can be disabled (to avoid cost) or enabled (to get faster satellite lock for 10 sen).

Once satellite lock had been achieved, the phone need no further assistance so no more data from Telco, hence no more further charges. The only exception is, should satellite lock be lost like going through tunnel, the phone may automatically (if AGPS is enabled) request satellite location data from Telco so another 10 sen charge.

I find the majority of people find GPS function useless or not important but should it be very important to you and especially if you need to use it while overseas, the undisputed king of GPS phone is Nokia. Period.