Moon+ Reader Pro 50% off until New Year's
This is among my top 5 favorite paid apps - nay, my top 5 apps period!
It's also, perhaps, the least fully appreciated due to its irrelevant name. Basically, I'm pretty sure it's the only reader on Play that reads every proprietary ebook/document format there is. It does this like a champ, providing cloud functionality for storing/accessing your books on things like Google Docs, etc. A full array of color customization options makes reading easy on the eyes.
Among its least obvious functions are not only its ability to read just about any conceivable document format you throw at it, but also to provide basic edit functions to unprotected documents.
I was also delighted to find it reads the less ubiquitous comic format (.cbt) and to allow text entry in those editable pdf forms you'll sometimes find.
At $2.50 it's a steal. It's normal 5 dollar price tag is way worth it, besides...
The Pro version can be purchased here: