# AppExtensionPoint.Identifier The details of an extension point that your app extension supports. ``` struct Identifier ``` ## Overview When creating a binding in your app extension, use this type to specify the extension point details. When binding to a host app’s extension point, always initialize this type with the host app’s bundle identifier and extension point name. ## Topics ### Creating an identifier attribute [`init(StaticString)`](/documentation/ExtensionFoundation/AppExtensionPoint/Identifier/init(_:)) Creates an identifier for binding to a system-defined extension point. [`init(host: StaticString, name: StaticString)`](/documentation/ExtensionFoundation/AppExtensionPoint/Identifier/init(host:name:)) Creates an identifier for binding to a host app’s extension point. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)