My question is...
Does the iOS operating system know the phone's location even if one could turn off the iPhone's built-in GPS module?
My understanding
some mobile web site has the functionality of "finding my device" that is achieved by dropping the SMS on the device from that Base station will pick the approx location of your device and you will be charged by your service provider this functionality can be achieved by Assisted GPS(A-GPS).
MileIQ app used the same method to get user location and some complex formula to calculate the distance.
What I don't understand
Does iOS, the operating system, can get the device location without GPS module as a service provider(Base Station) knows my device location.
Does cell tower or wifi hotspot transmit device location which is connected to it?
There is some theoretical answer for the iOS(swift) but none of them implement it to fetch the device location from cell tower or wifi.
Note I don't want to use CLLocation i.e default GPS module present in the device.
CoreLocation fuses together a number of sources to return a location for a device. This includes various sources that map the locations of SSIDs of WiFi base stations via GPS. For example, if you have location tracking turned on, you are crowd souring the locations of near by WiFi base stations and sending them to Apple anonymously. Third parties provide sources as well.
In addition, GPS can take awhile to triangulate your location. CoreLocation can get a rough location in a few seconds based on near by SSIDs, then report a more accurate GPS sourced location when available. This is sometimes called WiFi assist.
However, this functionality is part of CoreLocation, and requires the User to give your app permission to view the fused sensor data.