The BigRedButton is an ESP32 based, battery powered button which is publishing Wifi messages when it is being pressed. Supported message protocols are: UDP, HTTP, HTTPS, MQTT.
To use the BigRedButton, turn the key into the "on"-position and wait for a few seconds until it is connected to your Wifi. Then just press it :)
To configure the BigRedButton keep the Button pressed for a few seconds while turning it on. It should now boot in the configuration mode. In configuration mode the button acts as an Wifi access point with the name "BigRedButton". Connect to it (password is "BigRedButton") and open http://192.168.1.1/ in a browser. You will see a simple web page allowing you to change various settings.
The firmware can be compiled in and uploaded with PlatformIO.
ESP32 pin mapping: Pin 17 -> Button Pin, active low