Disclosed is an electronic device that is detachably coupled to a frame of a head-mounted device that can be mounted on a head of a user. The electronic device can consecutively perform tracking of the user's head using a sensor, when sensor data is abnormally received. Thereafter, if the sensor data is normally received from the head mounted device, the electronic device can consecutively perform the head tracking, enabling the user's action and the visual information to coincide with each other, thereby reducing inconvenience or misoperation which may occur in the case of the conventional head-mounted device.