Is there somewhere I can reference which platform APIs are available for each multiplatform target? For example for iOS

UIScreen

is available, but for macOS it isn’t available. I looked at the apple docs, and it says Mac 13+.

For your specific example,

UIScreen

is only available for iOS/iPadOS because

UIKit

is only on these platform. For macOS, it’s called

NSScreen

from

AppKit

framework. But

UIScreen

is available on macOS throught Catalyst but it’s not directly macOS.