LxReader

Open source e-book reader (GPLv3-or-later license).
Supported formats: fb2, fb3 (incomplete), epub (non-DRM), doc, docx, odt, rtf, pdb, mobi (non-DRM), txt, html, Markdown, chm, tcr.

Most complete support for FB2 - styles, tables, footnotes at the bottom of the page.
Extensive font rendering capabilities: use of ligatures, kerning, hinting option selection, floating punctuation, simultaneous use of several fonts, including fallback fonts.
Word hyphenation using hyphenation dictionaries.
Ability to display 2 pages at the same time.
Displaying and Navigating Book Contents.
Ability to use bookmarks
Reading books directly from a ZIP archive.
TXT auto reformat, automatic encoding recognition.
Background pictures, textures, or solid background.
Animation of turning pages - like in a paper book or simple shift.
Customizable actions for touch screen zones.
Built-in book library with search and/or filtering.
View illustrations with scrolling and zooming - by long pressing on the illustration.
Selecting text for copying to the clipboard, for the "Share" function, saving a bookmark, transferring to a dictionary application (or translator).
"Read aloud" function.

Homepage: https://gitlab.com/coolreader-ng/lxreader