I’m developing Swift Book Builder, a Mac and iPad book formatting app that lets writers publish their own books. The app is for writers who find Scrivener’s compiling process confusing and frustrating.
You can get your Scrivener project into Swift Book Builder by compiling the project to MultiMarkdown and importing the MultiMarkdown file into the app. Click the Publish button to get an EPUB book.
I have the app at a point where I can start showing it to people. You can download the Mac version and request a Test Flight invite to try the iOS version at the Swift Book builder site.