The tutorial guides the reader through creating a Twilio Voice Pricing Calculator using PHP. The calculator allows users to estimate the costs of voice calls for Twilio Programmable Voice, depending on the origin and destination numbers. The code includes forms for fetching number information and getting voice prices by origination number. The application uses the Twilio PHP SDK to connect to the Twilio API and retrieve pricing information. The tutorial also provides guidance on installing Composer globally and setting up environment variables for authentication. The complete code is provided at the end of the tutorial, allowing readers to test the application and extend it as needed.