A Node.js application was built to deliver new XKCD comics directly to users' phones via Twilio MMS. The app uses SuperFeedr to monitor the XKCD Atom feed for new entries and Firebase to store a list of subscribers. When a new comic is published, the app receives an notification from SuperFeedr, parses the XML content using xml2js, and sends out MMS messages to all subscribers in the list. The application allows users to subscribe by sending a "subscribe" message with their phone number, and users can also request specific XKCD comics to be delivered to them.