The Tumblr app is, admittedly, a wonderfully designed one. And there's no denying it has more functionality than something like Postcards. But for those who use Tumblr more as a means of finding articles to read instead zipping through streams of GIFs, this might be exactly what you're looking for.
Turns each post on Tumblr into individual "cards," which you can then swipe left and right to move backwards and forwards in your dashboard. As far as functionality, you can double-tap to like a post, hit reblog, or view all posts from a single user. And that's all there is to it.
Whether or not you'll be a fan of Postcards depends very much on how you use Tumblr as a whole. If you like to casually pass through pages of GIFs, pictures, and short little quips, this app probably doesn't make much sense. But flicking side-to-side is a fun, intuitive way to change up how you interact with your dashboard. And for someone who uses Tumblr to discover reading material, the lack of features brings along a welcome lack of distraction from your desired content. You can't create new posts, though. So if anything, Postcards is probably more of a nice enhancement to your Tumblr consumption—not a replacement.
Postcards, Download this app for: iOS, $2
The Best: Distraction-free browsing
The Worst: Highly limited functionality