Probably a stupid question, but how does this work technically, how does one correlate IP addresses to geolocation?

Data sources that provide geo coordinates and ip addresses. E.g. an app that sells its analytics data and you have geo access turned on.

How is this legal? IP + location is public info like looking up property ownership in Cali? Can we opt out if our data was sold under our noses without consent?

Congrats on winning in this space btw, site is super slick!