Since GPS is not available inside buildings due to the lack of line-of-sight to the satellite, systems for indoor positioning and navigation inside buildings must rely on other technologies. The most commonly used positioning technologies include Wi-Fi and Bluetooth Low Energy (BLE) beacons.
One advantage of Wi-Fi is that the access points are usually already provided. However, client-based localization of Apple devices is not possible using Wi-Fi. Beacons are easy to install, offer good positioning accuracy and enable client-based positioning of devices regardless of the operating system in use. The positioning accuracy can be further improved by the sensors integrated in the smartphone. Both technologies also have the advantage over GPS that they can detect the floor the user is currently on. This means that changes of floor can also be taken into account for navigation.