In this tutorial, learn how to build a real-time location tracking application using Hasura GraphQL Engine for backend, React, and Apollo for frontend. The app tracks the location of a vehicle in real-time by utilizing Hasura's GraphQL Engine real-time capabilities through subscriptions. Key data models include vehicles and their locations, with timestamps for each location update. The application includes four GraphQL operations: inserting a vehicle, inserting its location, subscribing to the vehicle location, and subscribing to the vehicle itself. Users can view the live app at realtime-location-tracking.demo.hasura.app, with the complete code available on GitHub.