Scrivener - Scrivener is a content-generation tool for composing and structuring documents.
Manuskript - Open-source tool for writers.
StoryMill - Developers and publishers of Mac, Win, and iOS productivity, home and office and writing software such as MacGourmet, Paperless and many more. Based in MN.
bibisco - bibisco is a novel writing software.
Novelize - Novelize is an online novel writing app designed to keep authors on track.
Hemingway - Hemingway App makes your writing bold and clear.