[marvindanig]

Those are file formats, as in both epub and PDF live outside of web (need to download etc.). Superbook format on the other hand lives on web. Each Superbook is a website. Huge difference!

PDFs are a skeuomorphic parallel of formatting that's natural to physical paper where as Superbooks adopt narrow column formatting of pure web with styling that scales responsively. Then there are granular differences in accessibility, new possibilities in layouts and content (webgl, AR/VR, CSS3, canvas art etc.), responsiveness, offline-first nature, iPad-first approach and usage of git for collaboration under the hood and a modern browser for final consumption.

To sum it up: Superbooks follow the most common convention and definition of a book. It is more 'consumer ready' than anything else on market.

[dragonwriter]

> Those are file formats, as in both epub and PDF live outside of web (need to download etc.).

You need to download any content to your browser to view it; otoh, online and in-browser renderers for both epub (which is mostly web tech in a package format) and PDF are ludicrously common.

> Superbook format on the other hand is a website. Huge difference!

Superbooks, on a quick glance through some, seem to have a visual look much like epub, the wasted space from aspect ratio mismatch of PDF, and the speed/responsiveness of cold molasses.

> PDFs are a skeuomorphic parallel of formatting that's natural to physical paper where as Superbooks adopt narrow column formatting of pure web with styling that scales responsively.

I don't see how PDF is any more skeumorphic than Superbooks (certainly, most PDF readers don't use skeumorphic—and dog slow—page turn animations.) You can, of course, design PDF with any fixed layout you want.

And AFAICT the main responsiveness Superbooks have is automatically choosing between single-page and two-page view based on screen aspect ratio/orientation.

I don't know what the “narrow column formatting” referred to is; the only webbish formatting I see is that pages seem to have symmetric bordering white space on left and right pages (but still have left and right pages distinguished, as in the version of 1984, by page number location.)

[marvindanig]

1. hm. 'webbish formatting' is exactly what I meant. These books are supposed to live on web, always above the fold, and yes, use the webbish format for good.

2. On value of page_number referencing vs. seeking people to use ids, classes and semantics: No, I think we are not on the same page here… ;-)

3. Speed/responsiveness: Page turns are @60FPS +/-5 give or take, and can easily be tuned/turned off from Settings. From analytics, you went in with an intent to surf the web capriciously and confused that with the intent to actually read a book, isn't it?