Sure, you can use it for whatever book you'd like to write. We've got one or two users who're using it for their poetry (which really gave me a problem, since I

Sure, you can use it for whatever book you'd like to write. We've got one or two users who're using it for their poetry (which really gave me a problem, since I designed the text to be suited for prose). Do note, however, that proper ebook conversion isn't ready yet. This is more minimum-viable product than anything else - if you log in you'll see a UserVoice forum filled with feature requests, which we're working on.