Amazon's Alexa voice assistant is found in many consumer electronic devices, and is a great way to get started with home automation. I recently purchased several Echo Dots, and while some of the came bundled with smart plugs that can turn my floor lamps into IoT devices, Alexa cannot be used for my home's overhead lights unless I purchase a new set of lightbulbs or rewire my light switches and install internet enabled relays. To solve this problem, I decided to use 3D printing and a NodeMCU microcontroller equipped with an ESP8266 chip to create a battery powered, internet enabled smart switch that can be easily mounted over the existing light switches in my home!
Interested in building a switch for yourself? Check out the following links: