Examples of embodiments provide systems and methods for varying the functions of an electronic device according to a physical relationship (e.g. the distance) between the electronic device and the primary user (e.g., owner) of the electronic device. The device may measure the distance using a wireless signal from a secondary device carried by or associated with the primary user. In some embodiments, the electronic device may change its functions based on its environment, in combination with the distance between the electronic device and the primary user. Environmental factors may include the device's location, the device's velocity, and the date and time of day.