1.Aldiko Book Reader (Rated:4.3)
Supported Formats: ePub, PDF and Adobe DRM encrypted eBooks
Aldiko Book Reader is a very simple android app for people, and you may find that most Android devices will pre-installed the it.With the user-friendly interface, you just need to load the books on your phone and create your bookmarks freely. Aldiko can automatically remember your reading position which can bring you back to where you left off.Besides, the app includes in-shopping experience with huge catalogs of eBooks.
Aldiko comes both in free and premium versions($2.99),but for the basic reading, you needn't to buy the premium version.
2.Kindle (Rated:4.2)
Supported formats: Kindle Books
Needless to say, Kindle is the most well known name for eBook reader.It not only offers free and paid eBooks,also, you can enjoy the magazines or newspapers from Kindle's store.One of the special feature of it is it has a built-in dictionary that allows you to look up words instantly while you’re reading your eBooks.Better, you can even borrow ebooks from your local library and have them delivered wirelessly to your Kindle app.
However, the interface of the app is not that good and kind of boring.Whatever, it is a great app for reading eBooks.
3.EBookDroid (Rated:4.6)
Supported formats:PDF, DjVu, XPS (OpenXPS), comics books (cbz,cbr), FictionBook (fb2, fb2.zip)
EbookDroid is a open source (GPL) app which can not only add bookmarks like most other readers in the market, but also give the outline of an ebook that doesn't have a table of contents.Apart from that, you can also jump to a page with standard "go to" feature.The best feature is the inclusion of OPDS catalog feeds, that means, you need to feed in the alias, URL, and authentication details to view an online catalog such as feedbooks.
Don't reading scanned books with this app as it will take a long time to load.In a word, the app is very nice,but if you just want to watch the common books, then just skip it.
4.FBReader (Rated:4.7)
Supported formats:epub, rtf, fb2 (.zip), mobi,plain text formats
FBReader is also the simle e-book reader app for your Android device with a straight, no-nonsense look.It has a browser/downloader for network e-book catalogs/stores or you can just download books manually and put them into /sdcard/Books catalog on your device.Also, the app is integrated with external dictionaries such as Fora Dictionary, FreeDictionary.org, LEO dictionary,etc.
FBReader can support multiple files and you can read them whichever font you choose to install.If you like this, then check out it.
5.Cool Reader (Rated:4.7)
Supported formats:eepub (non-DRM), fb2, doc, txt, rtf, html, chm, tcr, pdb, prc, mobi (non-DRM), pml
Designed to only read books, Cool Reader is very bare bones and basic, lacking any kind of shelf or main interface.The app has a clean white background and a old book type background by default.You can change them by going into the options menu.You can read books both in landscape and potrait mode and easily take notes and look words up in the dictionary.
Cool Reader just gives the impression of being very simplistic to people, and for a simple eBook reader app, this one worth to be check out.
Those are some Apps for Android Ebook Reader which I recommend. Perhaps you can found one that will suitable with Android Apps for you to use on your Android Tablet that can improve your experience in reading eBooks