These iPad-sized prototypes show when individual events are triggered or have sliders with which you can tweak different properties and settings.
They make it easier to understand what, for example, ‘originX’ does because you can change it together with ‘rotation’ and see the result.
To transfer the book: Connect your iDevice to your Mac, select the book in iTunes, and press ‘Sync’. The book’s read location will sync automatically between devices.
It’s a standard ePub 3 file, so it’s perfectly readable. The layout might seem a bit different though, because I formatted it for Apple Books.