The audio session categories available on the current device.
- iOS 9.0+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
Not every audio session category is supported on every device. For instance, the
record category is not available on a device that doesn’t support audio input.
Query this property to determine if the category you would like to use is available on the current device.