Scrivener is a word processor and project management tool created specifically for writers of long texts such as novels and research papers. It won't try to tell you how to write - it just makes all the tools you have scattered around your desk available in one application.
- Ulysses is WYSIWYM, while Scrivener is WYSIWYG. It can be extremely time-consuming to set the font styling right in every dialog box that controls the fonts. Ulysses, on the other hand, has one font setting, then the styles dictate how the editor is displayed. It's much more focused on content than appearance.
- Doesn't use Markdown format. Focus on tons of features instead of distraction-free writing.