SwiftUI

SwiftUI is a user interface toolkit from Apple designed to build UIs across Apple platforms using a declarative Swift syntax. Announced by Apple at WWDC 2019 and released with iOS 13 and macOS Catalina, SwiftUI provides a unified framework for developing apps on iOS, iPadOS, macOS, watchOS, and tvOS.

At the core, SwiftUI treats UI as a function of state. Developers describe views and their modifiers, and the framework renders the UI. Views are value types and are composed to form interfaces. Layout is managed with stacks (HStack, VStack, ZStack) and containers, with automatic support for safe areas and adaptive sizing. State management uses property wrappers such as @State, @Binding, @ObservedObject, and @EnvironmentObject to propagate changes.

SwiftUI emphasizes data flow in a unidirectional manner and often works with Combine for reactive programming. Features include live previews in Xcode, a rich set of built‑in controls, animations and transitions, accessibility support, localization, and styling via modifiers. Developers can also bridge to UIKit or AppKit components when necessary through UIViewRepresentable and NSViewRepresentable.

Limitations and considerations: SwiftUI is primarily available on Apple platforms; some APIs and controls may lag behind UIKit or AppKit, especially for complex tasks. Projects may require UIKit interoperability for mature apps. The framework has evolved rapidly; adopting it in existing projects may involve mixed code paths and careful architecture decisions; many teams use SwiftUI with the Model–View–ViewModel pattern and Combine-based data models.

Overall, SwiftUI provides a modern, readable approach to UI development on Apple devices, emphasizing composition, reactivity, and cross‑platform consistency while coexisting with older UI frameworks when needed.