WordPress has just released an Android app for writing articles for you blog. I am creating my first post by using the app right now. The app contains basic functions like bold, italic, link, and block quotes when entering text. You can add images, tags, and categories as well. I think it is a great tool to write drafts as shown here, but I would not publish posts directly from the app. You still need to perform your SEO stuff and other tasks like scheduling publishing from the browser.
Still, all-in-all, I have been waiting for WP to come out with this app. Based on how WP team has continually improve their software, this app is only going to get better with time. Nice job and thank you.