It’s called Wi-Fi Positioning System: https://en.m.wikipedia.org/wiki/Wi-Fi_positioning_system https://en.m.wikipedia.org/wiki/Wi-Fi_positioning_system There a

It’s called Wi-Fi Positioning System: https://en.m.wikipedia.org/wiki/Wi-Fi_positioning_system https://en.m.wikipedia.org/wiki/Wi-Fi_positioning_system There are both open and proprietary versions. I think early iPhones used it (with cell site data too), before they had GPS. Can’t remember their name for it. But, all big populated areas are mapped and understood. See Hybrid Positioning too, which is combining all available data, including Wi-Fi, to aid in rapid and accurate location information: https://en.m.wikipedia.org/wiki/Hybrid_positioning_system https://en.m.wikipedia.org/wiki/Hybrid_positioning_system