Over 1.5 million public domain books in the US (and over half a million outside the US) are now available for perusing on iPhone and Android devices. Just go to books.google.com/m in your mobile browser. You can search for a title, author, or subject. Or you can browse the list of "Featured books" and various categories like business and economics, the classics, science and math, travel, and more. Once you've picked out a book or two, you can easily get back to your selections by clicking on ...