You may not be the sort of person who fills out their Facebook profile with details like age, marital status, what high school you went to, hometown, but there

You may not be the sort of person who fills out their Facebook profile with details like age, marital status, what high school you went to, hometown, but there are hundreds of millions who do. just be correlating details like IP space geolocation, nevermind GPS/location API permission on a phone, with what pages a person likes, their biographical details, their friend network and the location data from those friends, advertising can get extremely targeted.