The tutorial covers building an Ionic app that allows users to make calls across three platforms (web, iOS, and Android) using the Vonage Client SDK. The project uses React as a frontend framework. To complete the tutorial, developers need a Vonage API account, Xcode 12 for iOS development, Android Studio with JDK 8 or newer for Android development, and Node.js installed on their machine. They also need to install Ionic and its dependencies, set up environment variables for Android development, create a Vonage application, generate a JWT for authentication, and configure the NCCO for making calls. The tutorial provides step-by-step instructions for running the project on each platform, including web, iOS, and Android, with minimal code changes required between platforms.