If you are looking for a good PDF or EPUB reader stop here you have found it. EBook Reader & PDF Reader is a highly customizable document viewer. It's optimized for Android devices.
EBook Reader & PDF Reader is an easy to use and highly configurable reading app that supports most popular document formats including: PDF EPUB EPUB3 MOBI DjVu FB2 FB2.zip TXT RTF AZW AZW3 CBR CBZ HTML XPS MHT and more. 
EBook Reader & PDF Reader  allows you to customize the way you read on a per book basis: each document's layout can be tailored to give you the best reading experience and all settings will be remembered the next time you will open it.
EBook Reader provides you with features to split pages automatically or manually crop margins and instantly zoom to a column's content.
Main Feature of Ebook Reader – PDF Reader:
✓ Easy document discovery with optional and configurable lists:
● Auto-Scan (with user selected folders)
● Browse (with an in-app file explorer)
● Recent (with a progress percentage bar)
✓ Ebook reader support for bookmarks annotations and quick-jump contents
✓ Individually configurable Day and Night modes
✓ Epub reader support for many popular translators and offline dictionaries
✓ Vertical scrolling lock
✓ Auto-centering of documents
✓ Single page view of dual paged documents
✓ Music mode with configurable scrolling speed
✓ Voice reading capability (via TTS Engine or "text to speech")
✓ Fast and easy document searching
✓​ ​Word search in multiple documents
✓ Online document format conversion
✓ Opening of files directly from archives (.zip)
✓ ​Right​ ​to​ ​left​ language support ​(Thai​ ​Hebrew​ ​Arabic etc.)
✓ Continue reading from where you left off
✓ Online Catalogs (OPDS) search and download books
✓ Much much more.....
Reading books of all formats: fb2 epub doc docx mobi prc txt rtf odt html. Also ereader allows you to read zip archives of ebooks.
Convenient loading of books into the reader from any folders of the phone and SD-card from the cloud or browsers.
EBook Reader – Epub Reader allows you to customize the way you read on a per book basis: each document's layout can be tailored to give you the best reading experience and all settings will be remembered the next time you will open it.
Open and read book files in EPUB PDF DOC RTF TXT DJVU FB2 MOBI and CHM formats. Supports chapters bookmarks page style. Automatically saves the current reading position. Automatic detection and display of the list of all supported documents on your device. DRM for EPUB and PDF formats isn't supported yet.