Firefox 9 Aurora for Android debuts some sweeping interface improvements. The Back button is now attached to the location bar, so it looks similar to the desktop Firefox. The location bar has been stretched so that the Refresh and Bookmark buttons are farther to the right and easier to reach on tablets. It puts Synced activity closer at hand, too. Mozilla anticipates this change will make it easier to use the browser on devices with larger screens, specifically tablets.
Tab implementation has been changed, too. You can swipe and hide the tab bar without being forced to show the tab thumbnail preview. The bar itself can be completely hidden, too, for full-screen viewing. This shows up best in portrait mode, where tabs appear in a list on the top left and keep them out of the way until needed.
Along with native camera app integration into the browser, developers will have an easier time validating certain types of input via new support for HTML5 automatic input validation. This feature makes validating certain types of input much simpler for developers.
Changes made to Firefox 9 Aurora can be read here.