This is a WiFi Smart Switch with the DIY capability that makes it possible to control connected devices via the eWeLink directly from your phone, or ask it to turn on/off devices with Amazon Alexa and Google Assistant. Amazingly, it has a DIY mode that is the firmware can be user-defined. Built-in a web server that exposes the REST AP, which allows you to connect the switch with your existing home automation system. Compatible with Vera, Fibaro, HomeSeer, Savant, Home Assistant, etc, for the protocol document and the code for the DIY Mode tool (updating), please go to http://developers.sonoff.tech/sonoff-diy-mode-api-protocol.html