---
title: identifier
framework: AVKit
role: symbol
role_heading: Instance Property
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+]
path: avkit/avplaybackuserinterfacetimelinesegment/identifier
---

# identifier

Optional external identifier for tracking or analytics purposes. May correspond to advertisement IDs, chapter markers, or other external systems.

## Declaration

```swift
var identifier: String? { get }
```