Great for following image-based tumblr feeds! – TumbleOn - View Tumblr Images Review

This is perfect if you primarily follow/reblog tumblrs that only post images, since it gives you a nice layout of thumbnails to browse through the posts on your dashboard and whoever you're following. Note that you shouldn't depend on this if you follow blogs that include a few text or video entries every so often that you'd be interested in reading. Since it's designed for image browsing, it omits any entries that don't at least have a picture. Another downside: while it is a universal app (yay!), it doesn't currently support syncing (so read entries on one device is still unread on another). The developers have said that this feature is coming soon though. Also: no portrait mode on iPad and no landscape mode on iPhone. I don't see these as deal breakers though, but you might.
Review by mrngoitall on TumbleOn - View Tumblr Images.