The Sonoff from Itead Studio is a fantastic little mains-switching module with a built-in ESP8266 and WiFi. If you want an easy way to control mains devices such as lamps and fans, this could be it!
Sonoff modules are preloaded with firmware that allows them to be controlled by a phone app, so they’re very easy to get started. But that’s just the beginning: using a USB-serial converter and the Arduino IDE, you can load your own software on the Sonoff and make it do your bidding. I used the Arduino IDE to load a sketch with MQTT support and OTA (over the air) updates, allowing it to be controlled by OpenHAB.
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