Location determination has never been so accurate
About 6 years ago as little as 5% of smartphones permanently had their GPS ‘on’. Today, because of thousands (if not hundred of thousands) of apps in use (which require GPS to be on), estimates and research suggest this percentage to be in the high 90’s (%).
This means a large portion of consumers have their GPS permanently on and with that, their exact location can be determined. This can be as accurate as 5 meters. It’s worth mentioning that, although developments are being made for the mobile-web protocol, only an ad-request coming from within an app - can ‘transfer’ a GPS position (or; latitude/longitude coordinates).
Although fraudulent activities are present (publishers selling their inventory with fake GPS coordinates because they are worth more), the technology is strong and many campaign strategies are possible. Advertisers can target consumers who are in the direct vicinity (footfall attribution) of their branch/store - name just one of hundreds of possible campaign strategies.
Read a case study about GPS targeting here.