An interface module is described for replacing a light switch assembly in an electrical switch box, the electrical switch box having an input wire coupled to a power source, an output wire coupled to a first lighting device, and at least one threaded bore. The interface module includes a housing, a first terminal mounted on the housing and connected to the input wire, a second terminal mounted on the housing and connected to the output wire, a first switch component configured to activate and deactivate the lighting device, a control configured to operate the first switch component, a user interface coupleable to the first terminal to receive operating power, and a wireless transmitter configured to transmit signals indicative of inputs received through the user interface, the wireless transmitter being configured to receive power from the first terminal.