I created this project to have a quick way of messaging my girlfriend. It's primary purpose is to either text her "On my way!" when I head out the door or "I love you" whenever I'm thinking about her. I wanted this to be as easy as pushing a button instead of having to unlock my phone, go to my messaging app, and type a message.
Each button is wired to a GPIO port on the Raspberry Pi. When a button is pushed, the circuit is completed, which sends a signal to the button's GPIO port. Meanwhile, a Python script runs continuously on the Raspberry Pi to listen for that signal. When a signal is detected, the script calls the Twilio API to send a text. A green LED indicates that the Twilio API was called succesfully and that the message was sent. A red LED indicates an error and that no message was sent.
You can view the code for this project and read more about the setup on this project's Github page: https://github.com/KevinBanana/RaspberryPiMessagingPanel