The goal of this project is to build a unit with four relays that can be controlled via Wifi. The components are mainly a ESP-03 wireless module, a ready-built relayboard and a 3V3 regulator. The software is developed in Arduino IDE and are based on the aRest-library (https://github.com/marcoschwartz/aREST-ESP8266). This library makes it very simple to build controlling interfaces, a few lines of code makes it possible to control the ESP's I/O via a web based interface. The web interface contains buttons to enable/disable the relay. It is also possible to send requests to the ESP to turn on/off the relay. If you put the following address in a webbrowser the Gpio12 turns high: http://192.168.1.121/digital/12/1 and low: http://192.168.1.121/digital/12/0 This can also be used with curl: curl http://192.168.1.121/digital/12/1 The ESP responds: {"message": "Pin D12 set to 1", "id": "1", "name": "esp8266", "connected": true} curl http://192.168.1.121/digital/12/0 {"message": "Pin D12 set to 0", "id": "1", "name": "esp8266", "connected": true} To be continued...