Andy Ihnatko's pick of the week on MacBreak Weekly episode 390 is a Hemingway style editor on the web. This is a style checker that uses the rules that the creators of the app feel Ernest Hemingway would have believed in. Just paste in your draft, and it will highlight the areas you could improve.
Hemingway can even tell you if sentences are too long and complicated. It shows whether you've used too many adverbs, and if you should use an active voice instead of a passive one. It also will tell you what grade reading level your writing is at. It's quite accurate too: when Andy submitted his first draft, it flagged most of the things he would have flagged on his own.
Andy doesn't feel you should be obligated to implement every suggestion Hemingway makes. He says your writing style shouldn't be defined by an algorithm. With this advice in mind, Hemingway can be a great tool to help you through the writing process.
Hemingway is a web-only app for now, but the developers are gauging interest in a full desktop version. Try out the Hemingway writing app for free at hemingwayapp.com. To hear Andy's recommendation on how to use Hemingway, check out MacBreak Weekly episode 390.