Apple's SwiftUI framework has revolutionised developing native iOS apps. Gone are the storyboards, XML files, and event handlers that you used to have to wrestle with – everything is created by writing Swift code. SwiftUI apps are built by composing state-driven views, and so how you handle state is key. I'll start with a brief tour of the anatomy of a mobile app – covering both the backend and frontend components. The bulk of the session will be devoted to a hands-on demonstration of building a simple chat app. The app lets users register, login and then join a chatroom of their choice. Once in a chat room, users can share messages with other members. While the app is simple, it solves some complex distributed data issues, with real-time syncing of data between your backend database and your mobile apps. Realm is also available for other platforms, such as Android, and so the same backend and data can be shared with all versions of your app.