In one aspect, a method is implemented for controlling a doorbell camera having a doorbell housing and a doorbell button mounted on a front cover plate of the doorbell housing. The doorbell housing contains a camera module, an LED indicator, a processor and memory including programs executed by the processor. The doorbell camera is electrically coupled to a remote chime via a bypass unit powered by a transformer that provides an input AC voltage. The remote chime is configured to ring in response to a user press on the doorbell button. A supply monitoring signal is generated based on the input AC voltage to indicate whether the input AC voltage is greater than a supply threshold. In accordance with the supply monitoring signal, the LED indicator displays on a surface of the doorbell housing one of a set of predetermined visual patterns, thereby sending a visual message to a user of the doorbell camera to indicate whether the input AC voltage is low with respect to the supply threshold. In some implementations, the camera module is configured to in accordance with a determination that the input AC voltage is not greater than the supply threshold, disable capturing images and exchanging data with a remote server, and enable communication with a client device via a short range communication link. Alternatively, in some implementations, the camera module is configured to activate a low power mode in accordance with a determination that the input AC voltage is not greater than the supply threshold. In another aspect of the application, an electronic device includes a device housing and a waterproof button assembly. The device housing encloses at least a plurality of electronic components and includes a front cover plate having an opening. The waterproof button assembly is formed in the opening on the front cover plate of the device housing.