[twodave]

They had to install the app and also consent to have their location tracked by the club. They could still use the app without that stuff, obviously, and the platform actually didn’t allow club admins to see where members were at all times—just which members were entering/exiting designated areas. It was actually quite a challenge to get that kind of information to the club in a timely fashion, especially if the club was situated near a busy roadway. You wanted the geofence large enough to give the club time to prepare to receive the guest, but not so large that it gave false positives for members simply driving past the club.

[laurent92]

Could you have pinged a server that only existed on the public wifi, and made the public wifi keyless?

[twodave]

An actual connection is not necessary for wifi to contribute to location accuracy. It just uses signal strength to available access points to triangulate. How folks like Google/Apple/etc. are able to get accurate location data for those access points is unknown to me.

[judge2020]

https://www.zdnet.com/article/how-google-and-everyone-else-g...

https://support.apple.com/en-us/HT207056#:~:text=If%20Locati....

TLDR Android & iOS Location Services will automatically contribute wifi data and correlate it with GPS. This can be audited to prove it's anonymously uploaded but it does happen.