Bluetooth beacons are hardware transmitters — a class of Bluetooth Low Energy (LE) devices that broadcast their identifier to nearby portable electronic devices. The technology enables smartphones, tablets and other devices to perform actions when in close proximity to a beacon. Bluetooth beacons use Bluetooth Low Energy proximity sensing to transmit a universally unique identifier picked up by a compatible app or operating system. The identifier and several bytes sent with it can be used to determine the device's physical location, track customers, or trigger a location-based action on the device such as a check-in on social media or a push notification. One application is distributing messages at a specific point of interest, for example a store, a bus stop, a room or a more specific location like a piece of furniture or a vending machine. This is similar to previously used geopush technology based on GPS, but with a much reduced impact on battery life and much extended precision. Another application is an indoor positioning system, which helps smartphones determine their approximate location or context. With the help of a Bluetooth beacon, a smartphone's software can approximately find its relative location to a Bluetooth beacon in a store. Brick and mortar retail stores use the beacons for mobile commerce, offering customers special deals through mobile marketing, and can enable mobile payments through point of sale systems. Bluetooth beacons differ from some other location-based technologies as the broadcasting device (beacon) is only a 1-way transmitter to the receiving smartphone or receiving device, and necessitates a specific app installed on the device to interact with the beacons. Thus only the installed app, and not the Bluetooth beacon transmitter, can track users. Bluetooth beacon transmitters come in a variety of form factors, including small coin cell devices, USB sticks, and generic Bluetooth 4.0 capable USB dongles. History and development The development of the "short-link" radio technology, later named Bluetooth, was initiated in 1989 by Dr. Nils Rydbeck CTO at Ericsson Mobile in Lund and Dr. Johan Ullman. The purpose was to develop wireless headsets, according to two inventions by Johan Ullman, SE 8902098–6, issued 1989-06-12 and SE 9202239, issued 1992-07-24. Since its creation the Bluetooth standard has gone through many generations each adding different features. Bluetooth 1.2 allowed for faster speed up to ≈700 kbit/s. Bluetooth 2.0 improved on this for speeds up to 3 Mbit/s. Bluetooth 2.1 improved device pairing speed