Soon after Android, Tumblr for iOS gets tablet support as well
Like its Android counterpart, the app does now have full tablet support, and looks great. But, unlike Android, the iPad version of Tumblr has a new radial menu for quick access to key functions. It's quite a bit like the UI you'd find in Path, if you've ever used that app. The radial menu has easy access to functions when you're composing a post, like adding a photo, video, link, etc.
If you want to give the app a shot, just head over to the iTunes App Store and grab it for free.