PubNub's tutorial provides a comprehensive guide on building a real-time geolocation tracking application using PubNub's Geolocation APIs and React Native, a popular mobile app development framework. The tutorial details the necessary environment setup, including creating a PubNub account, setting up development environments for iOS and Android, and installing essential packages and libraries like Node.js, React Native CLI, and the PubNub React SDK. Users can track multiple users on a map, toggle location permissions, and zoom into specific locations using the app. The tutorial also covers implementing user data aggregation and updating user data in real-time through PubNub's network, along with rendering the application’s UI and ensuring compatibility across different platforms. Additionally, it provides resources for further exploration of PubNub's integration with React applications, such as building chat apps and virtual events applications, with the final source code available on GitHub.