The author created a WebSocket-based demo application using React to display translated SMS messages in real-time. The application uses Nexmo's SMS service and Google Translate API to translate incoming SMS messages into multiple languages, which are then displayed on the screen. The application includes features such as a dropdown menu for selecting the translation language, a connection status indicator, and a component that displays the translated messages. The WebSocket server is created using Node.js and the `ws` package, and it establishes real-time communication with the client-side React application. The application demonstrates the use of WebSockets for bi-directional communication between the client and server, and it showcases the capabilities of Nexmo's SMS service and Google Translate API.