Its now a universal app with external keyboard shortcuts, new Activity and Stats tabs, support for Apple’s San Francisco font, and is available for $4.99 — 50% off of the regular price — for a limited time.
I’ve been begrudgingly using the previous version of Tweetbot on my iPad because it was still the best Twitter client available. The previous user interface was decidedly quaint, but Tweetbot 4 brings with it a modern aesthetic that I’m more than ready to switch to. Honestly, I would have paid $4.99 for the iPad update alone.
If you want a more in-depth look at all of the new features, I suggest reading Chris Gonzales’ review on The Sweet Setup.