The web app for Gmail, aka Gmail for mobile, has had a bit of a facelift. Which should be of particular interest to users of both iOS-based Apple devices and the BlackBerry PlayBook.It's not just about looks (although those have been improved too), there are new features here. For a start, there's a 'pull down to refresh' feature, allowing you to refresh your message list and conversation on all iOS and Playbook devices. To refresh it, simply touch the message list, drag downwards and release. Easy as that.Half way between looks and functionality is 'transitions'. When you tap on a conversation, tap back to the Inbox, go to the Menu or go back, the view will slide left or right. It just makes things look a lot smoother. Talking of looks, Gmail for mobile now has high resolution icons just for you iPhone 4 users. Yes, to take advantage of that Retina display, the icons and graphics are now at a higher resolution, making Gmail for mobile 'sharper'. Not exactly reinventing the wheel, but nice touches all the same. If you want to check it out first hand, you'll find Gmail for mobile here.