This tutorial demonstrates how to trigger a GitHub Actions workflow using Twilio SMS. To achieve this, one needs to create a Flask application that responds to Twilio's webhook requests and triggers the GitHub Action workflow by making a request to GitHub's API. The workflow is defined in a `.github/workflows/twilio.yml` file and listens for the `repository_dispatch` event with the type set to `twilio_sms`. Ngrok is used to make the application accessible over the web, and Twilio's Auth Token and Personal Access Token are used to authenticate the requests. The tutorial provides step-by-step instructions on how to set up the environment and test the application.