Leanpub is a free online publishing service for authors. Users can publish both in-progress and completed books, allowing them to get readers' feedback on the earlier versions. Authors can write using their preferred tools and then publish their manuscripts to PDF, iPad, and Kindle formats. Users can choose their own minimum and suggested prices, and they earn a 90% royalty minus 50Â¢ per sale. Users maintain all rights to their books and can choose to deal with a publisher at any time.