Twitter's official iOS app has been updated with a few nice new features. First off, it now offers an "enhanced sign up experience." iOS 5's built-in Twitter integration now allows apps to query the Settings app for sign-in credentials (if they've been set up to do so). This greatly streamlines the process of using an app with Twitter features for the first time, because you don't have to manually enter your account information or password when you first launch the app. Instead, you simply tap "OK" on a modal dialog popup that asks if the app can access your Twitter accounts. Tweetbot is the first third-party app I know of that's also integrated this functionality.
