As described in my last: they get a pretty good estimate from what APs you are close enough to see (the vast majority of users have wireless turned on 24/7, so

As described in my last: they get a pretty good estimate from what APs you are close enough to see (the vast majority of users have wireless turned on 24/7, so this is not using power by needing extra hardware to be working). If your settings are such that it is able, it will occasionally get a more accurate fix using GPS. > Does it rely on special APIs No APIs that I know of. Just having the relevant permissions out-of-the-box, and perhaps (caveat: guessing here) having an exclusion from being blocked by aggressive power management tools (Xiaomi devices are notorious for breaking background apps in the name of battery conservation, and it works well enough on mine despite it occasionally killing the podcast app I'm actively listening to, despite all the relevant “don't kill this” options/permissions being set). > or databases that other apps don't have access to? They have a database of AP locations which their own services use: https://support.google.com/maps/answer/1725632?hl=en-GB https://support.google.com/maps/answer/1725632?hl=en-GB Thinking about it, if the standard location APIs give access to this information with the same granularity, then a tracking app wouldn't need to be especially bright itself.