Beyond iBooks Author: Origami Engine Lets You Design Interactive Magazines Collaboratively | Mobile Publishing Tools |

Robin Good: If you are looking to an alternative to iBooks Author, Origami Design may fit perfectly that bill.  

From the official site: "Origami Design is a desktop application for Mac with all the tools you need to design interactive magazines, books, or other publications.

You can design the magazine/book/app by yourself or in collaboration with others. There is support for import and merging of projects.

The Design tool exports a content package bundle (similar to what you deliver to the in-App store) that can be dropped into iTunes and tested on the fly on the iPad through the Origami View app (Download it here:

The Origami View App is the viewer for the Origami Engine. It lets you preview, share and test creations made with Origami Design on the iPad."

The Origami publishing system works all in the cloud.

The system is currently in private Beta.

Find out more: and 

(Thanks to Marco Toscano for discovering this one)