[dx034]

Exactly, deactivating location sharing for apps that don't need it will help a lot. Wifis can still be located but tracking over mobile network won't really work. At least in London, IP geolocation of phone networks results in a large radius, too large for anything but long-distance travel.

And then you can (and should) obviously still use a VPN. The ad network can know it's a vpn and not necessarily present it as a location but they won't be able to guess you're real one.