After Tumblr acquired Tumblerette and the iPhone app got renamed simply "Tumblr" (catchy, eh?), the hip New Yorkers have updated it to version 1.2, with native reblogging, more photo-posting options, and even support for iOS4 multitasking. Those thoughtful guys.
A few bugs have been exterminated here and there, but the main thing is really the native reblogging, where you can pay dues to your friends' Tumblr-posts. Twitter support is now a given (if you want to annoy friends with updates, that is), and there's even German localization. I hadn't realized there were so many Germans using Tumblr. The app is free, and compatible with iPhones, iPod Touches and iPads. [iTunes via Tumblr Blog - Thanks, OMG! Ponies!]