UIKit.fx is the framework that provides the basic building blocks for user interfaces on iOS and tvOS. Its classes start with a UI* prefix.

Many concepts are shared by UIKit and its counterpart on Mac, AppKit.fx, but the classes are different &mdash some more than others. For example, both frameworks have a class to represent color that work very similarly, NSColor and UIColor, respectively, while other concepts are pretty unique to UIKit, such as its use of predefined controllers like UINavigationController and UITabBarController.

UIKit has differences (some minor, some very significant) between iOS and tvOS, but in general follows the same principles on both sub-platforms.

All types from UIKit.fx are exposed in the UIKit Namespace.

Some recommended topics in Apple's excellent documentation are:

See Also