Electronic devices are disclosed. According to the present invention, an electronic device may comprise a base; a rotor rotating on the base; a first magnetic body positioned at a center of rotation of the rotor; a second magnetic body having a different polarity from the first magnetic body, facing the first magnetic body, and positioned in the base; a first plurality of magnetic bodies positioned around the second magnetic body and having at least two different polarities; a hall sensor embedded in the rotor and sensing a change in magnetic property provided from the first plurality of magnetic bodies according to the rotation of the rotor; a wireless communication unit embedded in the rotor or the base; and a controller embedded in the rotor or the base and transmitting information obtained by the hall sensor through the wireless communication unit.