There is a new Android app that taps into Project Gutenberg, which is the largest archive of timeless classics and royalty free e-books. There are currently over 50,000 titles you can download to smartphone and tablet.
Gutenberg Books hit the Google Play Store a few months ago and has slowly been refined. There are animated page turns and lots of options to customize the reading experience.
There is a PRO version of this app, but instead of paying for it, all you need to do is leave a review. I think this is a sweet deal and draws attention to this great resource.