Bluetooth is an industry standard for data transmission over short distances between devices via radio technology. Using this standard, devices can be networked at a distance of about ten meters. Maximum ranges of 75 meters can be achieved. Bluetooth currently means Bluetooth Low Energy (BLE) in the context of location-based services. BLE distinguishes itself in comparison to the classical Bluetooth by a clearly reduced energy consumption. The Android operating system supports BLE since version 4.3 (mid-2013). Apple’s iOS operating system supports BLE since iOS 5. BLE is the wireless standard with which beacons communicate.