Does BrowserStack support Xamarin UI tests?

No, BrowserStack currently does not support Xamarin.UITest automation framework. However, you can test your Xamarin apps/forms on BrowserStack using Appium.

Reference information:

• Sample repositories for Xamarin apps/forms:
  • https://github.com/samirans89/xamarinforms-appium-test
  • https://github.com/BrowserStackCE/browserstack-examples-appium-nunit