That would be iBooks Author, right? http://itunes.apple.com/gb/app/ibooks-author/id490152466?mt=12 http://itunes.apple.com/gb/app/ibooks-author/id490152466?mt=

That would be iBooks Author, right? http://itunes.apple.com/gb/app/ibooks-author/id490152466?mt=12 http://itunes.apple.com/gb/app/ibooks-author/id490152466?mt=... (Which is no less proprietary or more cross-platform than HyperCard was, is aimed at creating content for Apple's walled garden platform -- iOS, that is -- and for the products of which the viewer app is given away free to Apple customers, just like HyperCard Viewer was back in the day.) TL:DR; it's an article from early 2010 and the author's belief was supported by a subsequent software release 15 months later. Whether he is provably correct remains an open question ...