The technology allows us with little additional piping to support iOS Storyboards.
We have an example here:
We do not plan to push that main-stream, as we are working on our own UI markup.
We may (or may not) device a facility that will generate Storyboards from subset of our markup for the WatchKit.
As for native Android views, currently NativeScript for Android doesn't support XML layouts. However, NativeScript comes with cross-platform XML layouts (http://docs.nativescript.org/ui-with-xml)
which is similar to Android XML layouts. Also, we are actively discussing whether and how to provide support for existing platform specific layouts (Android, iOS and Windows Phone in future).
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