The default quality-of-service class.
- iOS 8.0+
- macOS 10.10+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
- Xcode 6.0.1+
Default tasks have a lower priority than user-initiated and user-interactive tasks, but a higher priority than utility and background tasks. Assign this class to tasks or queues that your app initiates or uses to perform active work on the user's behalf.
The quality-of-service class for user-interactive tasks, such as animations, event handling, or updating your app's user interface.
The quality-of-service class for tasks that prevent the user from actively using your app.
The quality-of-service class for tasks that the user does not track actively.
The quality-of-service class for maintenance or cleanup tasks that you create.