In some embodiments, an apparatus includes an antenna, an energy storage device, a receiver, and an indicator assembly. The receiver may be coupled to the antenna and the energy storage device. The receiver may be configured to receive wireless energy via the antenna such that an energy storage level of the energy storage device is increased. The indicator assembly may be coupled to the receiver and may be configured, in response to the receiver receiving the wireless energy, to provide an indication based, at least in part, on a characteristic of the wireless energy.