MobileRead Forums - View Single Post - Mobi or epub-which do you prefer?

tomsem · 06-24-2011, 11:55 AM

I have not experienced a reader that 'supports both' (unless you count separate apps on iOS). Notably Kobo Touch says that it does, but seems to have some issues with mobi; it's probably not a very good implementation, which does not reflect one way or the other on mobi. And of course there are a number of others that support both, though they don't have the brand recognition of Kindle/Nook/Sony/Kobo.

For the most part, mobi is a subset of ePub, so ePub is 'better'.

One exception is that mobi defines tags that can be used to create lookup dictionaries, so you can add additional dictionaries to the reading system, and even author new ones yourself. None the ePub reading systems I've seen have this capability, and so you are restricted to whatever dictionaries the reading system comes with.

But everything else leans in favor of ePub:
- ability to embed fonts, with broad reading system support
- most ePub reading systems support NCX TOC, which provides a way to navigate a multi-level TOC without jumping to another part of the book and navigating hyperlinks. mobi (or at least the Kindle implementation) uses this also, but the implementation only uses it for easier navigation between adjacent chapters.
- drop caps, right justification options, SVG (scalable) graphics, floating images are broadly supported by ePub reading systems.
- tables work better

An epub file contains all the source code, so (without DRM) anyone can open it up and modify styling, correct typos, etc. Mobi is a binary format, and does not contain all of the information of the original source code. There are tools to reverse-compile, but you don't get CSS or NCX back, so it is harder to fix some issues.

Of course the relative strengths of ePub can be neutralized if the reading system doesn't support those features, and unfortunately some implementations are very weak (don't support SVG, don't support embedded fonts, hyperlinks, or NCX navigation), while others, like iBooks, offer extended features. So ebook designers often have to make compromises or prepare more than one 'standard' ePub format, depending on the target system. By contrast, mobi pretty much means 'Kindle' these days, and there are fewer of these considerations to sort through.

Finally there is the market reality that mobi is used on the most popular platform (Kindle). You could say that makes mobi 'better'. However I think that is only true in the short term, and Amazon will have to adopt ePub eventually to maintain (or to extend) their dominance.

I prefer the Kindle ecosystem and feature set, but prefer ePub as a format. For now that means having one ereader for each, and finding ways they can complement each other. I'm reading a lot of library books in ePub format, but my purchases are still mostly Kindle format, though I'm making fewer of them.

06-24-2011, 11:55 AM	#11
tomsem Grand Sorcerer Posts: 6,955 Karma: 27060153 Join Date: Apr 2009 Location: USA Device: iPhone 15PM, Kindle Scribe, iPad mini 6, PocketBook InkPad Color 3	I have not experienced a reader that 'supports both' (unless you count separate apps on iOS). Notably Kobo Touch says that it does, but seems to have some issues with mobi; it's probably not a very good implementation, which does not reflect one way or the other on mobi. And of course there are a number of others that support both, though they don't have the brand recognition of Kindle/Nook/Sony/Kobo. For the most part, mobi is a subset of ePub, so ePub is 'better'. One exception is that mobi defines tags that can be used to create lookup dictionaries, so you can add additional dictionaries to the reading system, and even author new ones yourself. None the ePub reading systems I've seen have this capability, and so you are restricted to whatever dictionaries the reading system comes with. But everything else leans in favor of ePub: - ability to embed fonts, with broad reading system support - most ePub reading systems support NCX TOC, which provides a way to navigate a multi-level TOC without jumping to another part of the book and navigating hyperlinks. mobi (or at least the Kindle implementation) uses this also, but the implementation only uses it for easier navigation between adjacent chapters. - drop caps, right justification options, SVG (scalable) graphics, floating images are broadly supported by ePub reading systems. - tables work better An epub file contains all the source code, so (without DRM) anyone can open it up and modify styling, correct typos, etc. Mobi is a binary format, and does not contain all of the information of the original source code. There are tools to reverse-compile, but you don't get CSS or NCX back, so it is harder to fix some issues. Of course the relative strengths of ePub can be neutralized if the reading system doesn't support those features, and unfortunately some implementations are very weak (don't support SVG, don't support embedded fonts, hyperlinks, or NCX navigation), while others, like iBooks, offer extended features. So ebook designers often have to make compromises or prepare more than one 'standard' ePub format, depending on the target system. By contrast, mobi pretty much means 'Kindle' these days, and there are fewer of these considerations to sort through. Finally there is the market reality that mobi is used on the most popular platform (Kindle). You could say that makes mobi 'better'. However I think that is only true in the short term, and Amazon will have to adopt ePub eventually to maintain (or to extend) their dominance. I prefer the Kindle ecosystem and feature set, but prefer ePub as a format. For now that means having one ereader for each, and finding ways they can complement each other. I'm reading a lot of library books in ePub format, but my purchases are still mostly Kindle format, though I'm making fewer of them.