I've never actually been able to get a confirmation one way or the other oh which of Google's native apps are "hybrid" apps and just how much of those apps is done in HTML5. The previous version of their gmail app seemed to employ a lot of HTML5 because you could see the main inbox list re-render occasionally. That app performed perfectly well for me. Unless we hear from Google officially about the new app we'll never know. It could be that it's full native, or it could be that they've perfected the HTML5 code to make it feel completely native. Who knows.