US Patent 9774995 Location tracking based on overlapping geo-fences

A system for controlling a device to track the location of the device is provided. The system identifies an initial location of the device. The system then identifies a plurality of areas having different sizes. Each area encompasses the identified location. For each of the areas, the system registers the area with a location provider to receive a notification when the location provider detects that the device has left the area. Upon receiving a notification that the device has left an area, the system may repeat the process of identifying the location and the areas and registering the areas to continue tracking the location of the device.