iBeacon is a protocol developed by Apple and introduced at the Apple Worldwide Developers Conference in 2013.[1] Various vendors have since made iBeacon-compatible hardware transmitters – typically called beacons – a class of Bluetooth Low Energy (BLE) 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 an iBeacon.[2][3]

iBeacon is based on Bluetooth low energy proximity sensing by transmitting a universally unique identifier[4] 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,[5] track customers, or trigger a location-based action on the device such as a check-in on social media or a push notification.

iBeacon can also be used with an application as an indoor positioning system,[6][7][8] which helps smartphones determine their approximate location or context. With the help of an iBeacon, a smartphone's software can approximately find its relative location to an iBeacon in a store. Brick and mortar retail stores use the beacons for mobile commerce, offering customers special deals through mobile marketing,[9] and can enable mobile payments through point of sale systems.

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freeradical wrote:
Why would someone have a Dunkin Donuts app on their phone?