Twitter has rolled out a new version of its iOS app which adds support for push notifications. That means you can receive pop-up messages letting you know when a Twitter user sends you a direct message or posts a tweet with an @mention for your username.
Depending on how you use Twitter, this can be either extraordinarily useful, or a pain in the behind since it could mean an endless stream of pop-up notifications.
Twitter 3.2.1 for iOS also includes additional retina display graphics, one-tap geotagging, some bug fixes, and better display of shortened URLs.
The Twitter app is available as a free download from the App Store.