Geo-fencing is a technique that uses mobile location services to reach consumers in real-time when they are around a store location or point of interest, also known as a geo-fence.
Geo-fencing also includes targeting group development; accumulating groups of people who share similar characteristics based on their history of movement into and out of various geo-fences.
If a consumer has opted into location services on their mobile phone and enters within this fence, geo-fencing allows you to trigger an advertisement or message to that consumer in an effort to influence their behavior.
For example, if you are a restaurant and you want to target consumers shopping in a nearby grocery store, you could set up geo-fencing around nearby grocers so when consumers walk into those places, they will be served your advertisement.