[luketaylor]

Not an exaggeration—Apple’s primary “location services” API, used on iOS/macOS, is just a lookup table for wireless APs’ MAC addresses. [1]

WiFi scanning is much less power intensive than GPS, much more reliable indoors, and often (in dense areas) more accurate even outdoors. iirc the iPhone only connects to “real” GPS in specific situations, such as when visible wifi signals are insufficient (e.g. highway driving).

[1]: https://www.appelsiini.net/2017/reverse-engineering-location...