Ebooks are readable on most smart phones and laptop/desktop/tablet computers through installing free e-reader and library management software. Here are some of the best options
|Calibre||Desktop/Laptop library management, reading, and device sync. All formats supported.||Mac OSX, Linux, Windows|
|Kindle||Amazon buying/reading applet. Kindle only supported.|
|Nook||Barnes and Noble buying/reading applet. Epub only.||iPad, iPhone, Android, Windows, Blackberry, Mac OSx|
|Mobipocket||Reading software for almost every device imaginable.||Software browsing and downloading for all devices|
|Aldiko||Arguably the best e-reading software for Android||Download page|
Finally, <a href=http://www.ebookmall.com/knowledge-collection/mobipocket-faq.htmclick here for everything you ever wanted to know about the technical end of ebook formats.