Location data
Location data shows where a device is or has been, and is used in advertising to understand which places people visit and to build audiences from that.
It comes from a phone’s GPS, wifi networks, Bluetooth beacons or the mobile network itself, and reaches advertising through apps and SDKs that collect it with the user’s consent. Its accuracy varies widely depending on the source, from a few metres to several hundred.
Handled properly (anonymously, in aggregate and with permission) it shows what kinds of places an audience visits, makes it possible to run campaigns near a point of sale and to measure whether people who saw an ad later went to the store. The GDPR treats it with particular care, because a person’s movements say a great deal about them.
