Definition: geofence

A geographic zone that is defined for tracking purposes. When a tracking device in a vehicle or a person with a smartphone tracking app enters or leaves a geofence, the device sends a signal via email or texting to a recipient. Geofences can be permanently assigned; for example, a neighborhood geofence enables a thermostat to raise or lower the temperature when people leave home and come back. A temporary geofence might be assigned to ensure teenagers do not stray from a venue such as after being dropped off at a concert.