The text post publishing tool for serious tumblogger.myTextPost for Tumblr?! Yes, I know - some WP user will smile. But there are so many people out there, using Tumblr for much more than re-blogging annoying GIFs. Mind the New Yorker-Tumblr for example.
And for us the Apps with 'pro' features for writing text posts - well, there is not a single one out there. Even my own myTumblr lacks some features serious blogger sometimes may need.
That's why I've written a completely new App for Mac for all out there, using Tumblr for writing awesome articles and entries.
TextPost is - well, for text posts :-)
It supports simple formatting like bold or italic, you can use HTML or even Markdown and open existing Text, HTML and Markdown Documents - thus you can even pre-write your articles with an App like myTexts pro.
Of course you can preview the text you are working on at any time. Published posts can also be 'web-previewed' at any time without leaving the App and because blogging often means to work with web-finds, other articles etc. - I've extra added support for our Read It Later bookmarks.
And of course you can also access already published posts and because many of you really use the draft feature, they can also be accessed with ease.