Roon.io is a Responsive, Minimalist Blogging Platform That's All About Writing
The blog is responsive, so it will works just as well on a desktop as it does on a smartphone.
Roon.io is focussed on the writing experience. The text window is the largest part of the page and once you start typing in it, all other elements of the page get greyed out, giving you a distraction-free writing interface. It's really quite cool.
Text formatting tools can be used through keyboard shortcuts, you can add images (only uploaded from your hard drive, no direct web links), and save drafts to be published later.
Try it out, Roon.io is free to sign up.