For AT&T customers, the myAT&T app serves as a mobile portal into their cellular accounts, a place to view usage, curse, and make payments (though not necessarily in that order). Version 3.0 has rolled out a new UI, and while it does look better than the previous version, it's still just a mobile web page with an app wrapped around it. Slideout menus are pretty and convenient though (perhaps even pretty convenient), so the app gets points for having one.
Twitter continues its march towards being taken seriously as a social network with today's update to its mobile app that brings some interesting new profile additions. For starters, header images. With Facebook and Google+ beginning the trend, it seems a social network can't have just a profile picture anymore. Everyone who's anyone has a profile picture, and a hero image.
Curiously, the header images can only be added via the mobile app itself.