It is a series of videos showing how to integrate your smart devices (esp8288, esp32, arduino) with Google Smart Home (Assistante and Home app). The first 2 videos shows how to set up your own service application that interfaces with Google Smart Home, this application was based in a Google Java end to end sample. This was modified to add a MQTT layer, so every action on Google Home or Assistant ends up in a MQTT message to your smart device (esp8266 for instance). Then it is up to your code to act on this message and turn on/off things, change temperature set points, change light color/brightness, etc. Hope you enjoy and make your own smart devices!!