An electronic device includes a body, a rotatable member, a projecting unit configured for projecting an image, a sensing unit and a processing unit. The body includes a connecting end, and a plurality of conductive contacts is formed at the connecting end. The rotatable member is rotatably connected to the connecting end. The rotating member includes a conductive ball configured for being electrically connected to one of the plurality of the conductive contacts, and the plurality of conductive contacts are formed along a displacement path of the conductive ball. The sensing unit is configured for sensing interactions at specific locations corresponding to the projected image. The processing unit stores a plurality of images, and is configured for controlling the projecting unit to project a corresponding image according to the conductive contact which is electrically connected to the conductive ball.