Twitter released an update to its official iOS client today, adding an improved sign up experience, integration with Twitter’s own picture service, and a redesigned Direct Message view on the iPad. As we detailed with our coverage of Tweetbot 1.7 earlier today, iOS 5 is now allowing developers of Twitter-enabled apps to fetch account credentials directly from the iOS Settings app, rather than forcing users to re-authenticate with their accounts every single time. The official Twitter client, as we expected, implemented iOS 5’s single sign-on to allow users to get already-configured accounts from the Settings. The feature is optional and new accounts can still be added manually, but as I wrote with the Tweetbot update, it’s very convenient to be able to add accounts without entering usernames and passwords anymore.

Also new in Twitter 3.5 is direct upload of photos to Twitter’s photo sharing service, available at pic.twitter.com. This can be configured in Twitter’s Preferences both on the iPhone and iPad. What’s new to the iPad is a much improved Direct Messages interface, which has been updated to order DMs chronologically and by thread with a new clean design. Gone is the DM popover from the app’s sidebar, too. iPad owners can now also tap on a location to show tweets nearby.

Twitter 3.5 is available on the App Store now.