EPUB
http://gizmodo.com/5478842/giz-explains-how-youre-gonna-get-screwed-by-ebook-formats
https://en.wikipedia.org/wiki/EPUB
Major players
Amazon
Format: AZW, MOBI
Device: Kindle
Current market share of US ebook sales: 60%
Barnes & Noble
Format: EPUB
Device: Nook
Current market share of US ebook sales: 25%
Apple
Format: EPUB
Device: iPad, iPhone
Current market share of US ebook sales: 10%
http://rhystate.com/ebook-formats/
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