---
title: App extensions
framework: uikit
role: collectionGroup
role_heading: API Collection
path: uikit/app-extensions
---

# App extensions

Extend your app’s basic functionality to other parts of the system.

## Topics

### Extension support

- [NSExtensionRequestHandling](foundation/nsextensionrequesthandling.md)
- [NSExtensionContext](foundation/nsextensioncontext.md)

### Document provider

- [NSFileProviderExtension](fileprovider/nsfileproviderextension.md)
- [UIDocumentPickerExtensionViewController](uikit/uidocumentpickerextensionviewcontroller.md)

### Custom keyboard

- [UITextDocumentProxy](uikit/uitextdocumentproxy.md)
- [UIInputViewAudioFeedback](uikit/uiinputviewaudiofeedback.md)
- [UIInputViewController](uikit/uiinputviewcontroller.md)
- [UILexicon](uikit/uilexicon.md)
- [UILexiconEntry](uikit/uilexiconentry.md)

## See Also

### App structure

- [App and environment](uikit/app-and-environment.md)
- [Documents, data, and pasteboard](uikit/documents-data-and-pasteboard.md)
- [Resource management](uikit/resource-management.md)
- [Interprocess communication](uikit/interprocess-communication.md)
- [Mac Catalyst](uikit/mac-catalyst.md)