Quark release a new manual called “Digital Publishing with QuarkXPress 2016”.
It can be found here and describes how to create app content for native apps, ebooks in the EPUB2 and EPUB3 format (reflow and fixed-layout) and HTML5 Publications:
Both an engineer and a layout artist, Matthias bridges the gap between technology and people.
Before joining Quark, Matthias pioneered print, Web, and multimedia products for multiple German publishing companies. Since 1997 he has played a central role in shaping Quark’s desktop and enterprise software.
Starting 2003 Matthias has focused on Quark’s interactive and digital publishing solutions. He is an active participant in design and publishing communities and represents Quark in the Ghent PDF Workgroup.
Since February 2014 Matthias heads Quark’s Desktop Publishing business unit and is therefore responsible for QuarkXPress.