Bluetooth Low Energy Beacons are Bluetooth devices that broadcast their universally unique identifiers (UUIDs) in proximity. They are low-power devices attached to some physical object (such as a wall or an electronic device), which detects the nearby device (typically a cellular phone) and triggers some behavior. These behaviors normally contain a location-based task or a unique broadcast that can be preprogrammed on the beacons before deployment. Beacons assume that each person has a Bluetooth Low Energy device already listening to beacon calls and that the broadcasts will be received by them. In this chapter, we will use the Estimote as our primary Bluetooth beacon; it looks like this:
