This week’s assignment was to create an app using Expo and Firebase, and use it to interact with a wirelessly connected ESP32. I spent 5 hours attempting to get my ESP32 to connect to wifi, even going as far as building an LED diagnostic board due to jumbled serial output. This was all for nothing though, as once I plugged everything into a different ESP32, it connected to wifi immediately.
I spent so much time troubleshooting, I wanted to give myself an easy project. I took a 4.5v battery pack, a resistor, and a piezo-buzzer, and directly soldered them to the board. I used hot glue to fix the battery to the back of the board. This relatively small form factor allows the device to be hidden in the room of someone you would like to torment. The app displays one button, which turns off and on the buzzer. This way, you can watch as the victim searches for the device, only for it to turn off when they get close enough, then back on when they give up.