iTwitter has no shortage of rival Twitter apps on iPhone, but it's the first to offer push notifications.
The app, which launched this week, looks much like most of its competitors, letting users access their Twitter account on the move from their iPhone.
However, it uses the push notification feature in the iPhone 3.0 software to let users know when they have new direct messages or public replies, even when they don't have the app open.
Well, sort of. The push feature only works for messages and replies that have been posted using iTwitter - so they won't be pushed alerts for any friends who are using different apps, or the Twitter website.
Not such a useful feature, then. However, it does show the potential that push notifications can bring to social networking apps on iPhone.
Rivals like Tweetie, Twitterfon and TweetDeck will presumably be following suit with push as soon as they can incorporate it.