Thank you for writing and for raising this question.
While UI for Xamarin is built on top of UI for iOS and UI for Android, it is not intended to be used as a bundle of UI for iOS, UI for Android and UI for Xamarin controls. The UI for Xamarin product does not ship the respective libraries their plain form and we do not provide support for UI for iOS and UI for Android if you hold only a UI for Xamarin license. Therefore, in your situation, you will need to purchase a separate UI for Xamarin license for your Xamarin-related development, while still keeping your UI for iOS and UI for Android licenses active.
I hope this clarifies the question.
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