Good news for anyone with an Android phone. It also doubles as an eBook reader. Yes, I know, it's a small screen. However, if you try out an eBook reading app, you may discover that your DROID, EVO, or Galaxy turns out to be a pretty good pocket reader. There are also at least three popular eBook devices that have compatible apps for your phone, so if you decide you'd like a larger screen later, you can still access your electronic library.
Want free books? You can download free eBooks for every one of these readers. Most books are classics now in public domain, but you'll also find the occasional promo.
1. The Kindle App
Amazon.com's Kindle reader is a huge hit. One of the things that makes it so popular, aside from access to a huge library of Kindle books on Amazon.com, is that Amazon.com offers an app for most mobile devices, including: Android, iPhone, and laptops runing Windows or Mac OS. The Kindle app also remembers where you left off from any Internet-connected device, so you can start reading on your iPod and finish on your Android.
The thing to keep in mind as you build an Amazon.com library is that Amazon's books are meant to stay in Kindle readers. They use a proprietary format rather than keeping with industry-standard ePub format, and that locks you into only buying books from Amazon.com.
2. The Kobo App
Kobo Readers are supported by Borders bookstores. They can read ePub formatted books as well as Adobe Digital Editions, which means you can potentially use them to check out books from the library. Kobo has some traditional eBook readers and a few Android-based color tablets. It also allows you to loan books to other Kobo owners, although the Android app does not offer this feature at this time.
The Kobo Reader ships with 100 free eBooks, most of which are public domain classics. You can also buy books outside the Kobo store, so long as they are DRM-free ePub books.
3. The Nook App
The Nook Reader is Barns and Noble Books' eReader. It comes with either a mainly black and white e-Ink display and color strip on the bottom or as a full color tablet. Nook uses a modified version of Android, so it's unsurprising to learn that you can get the Nook app to run on your Android phone or other device. Nook, like Kobo, supports ePub and Adobe Digital Editions. The new Nook color reader also allows you to download apps.
If you don't want an app tied to a major bookstore, but you do want a full-featured reader capapble of reading open ePub books, Aldiko is a solid and popular choice. It's easy to read, and very customizable. However, unlike the other readers mentioned here, it is not tied to a tablet, and it doesn't sync with a reader. You could run the Aldiko app on an open Android tablet, but your bookmarks will not transfer to your phone.
Google eBooks is a bookstore from Google. They have supported apps for Android, iPad, iPod, computers, and just about every smartphone or eBook reader available, except for the Amazon Kindle. The Google eBook reader offers similar features to most readers, including the ability to start reading on one connected device and continue on another. The bookstore itself features a large selection of free books that use Google Book's large database of scanned public domain library books.