According to this link: App Tracking Transparency Dialog does not appear on iOS,
RequestAuthorizationTracking()
should be called in:
applicationDidBecomeActive()
(See answer by El Tomato in that thread.)
Especially for iOS 15+. But in Unity the closest method is
public void OnApplicationFocus(bool focus)
But this is not called when the app starts up (on actual iOS device and in iOS Simulator), only when it goes to background and then foreground again.
So where should this code go:
ATTrackingStatusBinding.RequestAuthorizationTracking(this.DidCompleteAuthorizationTracking);