At Google's I/O conference held a couple of weeks ago, a session called "Structure in Android App Design" was held that talked about creating more efficient, cleaner-looking apps. Within, a screenshot of Google's Gmail mobile app was shown, and the eagle-eyed folks at Android Police happened to notice a couple of differences.
While some believe that this leaked screenshot could be nothing more than a mockup, the writer at the site believes wholeheartedly that it's not. The biggest reason is thanks to the Google employee's email address being exposed - you wouldn't use a real email address in a mockup.
If this is indeed a sign of an upcoming update, it's going to make Gmail for mobile a lot more efficient. There's a new navigation drawer spawned by pressing three little dots to the top-left. It slides in from the left, and is likely to be scrollable. Users of Gmail on tablets already have a similar design, except here, the labels list wouldn't remain stationed on the side - it'd overlap your emails so that they have more room to breathe (and you can read a larger preview of the contents).
Also changed seems to be the bottom action menu, which previously allowed you to refresh, manage labels, search and so forth. A couple of those functions are immediately available at the top in this presented screenshot, and we'd assume that pushing the three buttons on the right would reveal the rest.
Overall, these changes are small, but they look to greatly optimize Gmail. I still yearn for further updates, however. The lack of being unable to turn conversation view off for mobile has long driven me bonkers. And especially on a phone (but even on a tablet), it's too easy to accidentally go into an email when trying to mass select emails to purge. And whatever happened to the "Mark Unread" option?