objective c - Question regarding GPS/Location in iPhone -

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currently i'm doing location app in iphone question is....

what service iphone using?

according apple developer manual "the framework uses information obtained built-in cellular, wi-fi, or gps hardware triangulate location fix device."

so either built-in cellular, wifi or gps hardware, how ensure uses gps hardware location?

because app requires accurate location.

to limit supported devices ones gps can use uirequireddevicecapabilities in app's plist. way (to knowledge) force device using precise location determination (in case gps) set desiredaccuracy , distancefilter of cllocationmanager accordingly.


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