You may want to follow this thread: Support building native Android applications with Dart

https://code.google.com/p/dart/issues/detail?id=19266

Would be neat if they had an adapter for the polymer stuff so that a "material" UI could be rendered in a webpage or with Android's native UI depending on the execution context and no changes to the app code (written in Dart). On the edge of possible, but a lot of work.

That should work as of this week with Polymer's paper-elements: http://www.polymer-project.org/docs/elements/material.html, available for Dart at https://github.com/dart-lang/paper-elements.

You could either build it as a mobile web app, or if you need more of Android's APIs there's https://cordova.apache.org/.