Tweetie, an iPhone application which acts as a mobile client for micro-blogging service Twitter, has issued an update which brings it to version 2. We've mentioned the app in the past as coming soon, but now it has arrived and it's live in the App Store.

There's a whole pile of new features, but the biggest are that it now has persistence (it remembers where you were when you switch it off), new message indicators, the ability to save draft tweets, speed boosts, cached tweets for offline reading and the ability to drag up to refresh - rather than hitting a refresh button.

Annoyingly the update isn't free for existing Tweetie users. It'll cost you £1.79 (or $3 in the States) to upgrade, whether or not you bought the original version. That hasn't proved popular, but most reviews (including ours) reckon that it's worth the outlay - less than the price of a pint.

Go grab it, and let us know what you think in the comments below.