Recently, [Edward Schmitz] wrote in to let us know about his Hackaday.io project: SigCore UC: An Open-Source Universal I/O Controller With Relays, Analog I/O, and Modbus for the Raspberry Pi. In the ...
So you want to control some mains electrical (or lower voltage) item using your phone, perhaps? This single ESP8266 plug-in controls a relay that is built in to the module. An Android app (.apk) ...