Moon+ Reader v10.7

Moon+ Reader has been around for years and it's still one of the most customizable ebook readers on Android. It supports nearly every format you can throw at it — EPUB, PDF, DJVU, AZW3, MOBI, FB2, PRC, CHM, CBZ, CBR, DOCX, ODT, RTF, TXT, HTML, Markdown, WEBP, RAR, ZIP — plus online libraries through OPDS and your own Calibre server. Where it really shines is control: 10+ built-in themes with a day/night switcher, fonts and spacing you can tune in detail, 24 customizable gestures and key actions, five auto-scroll modes, and a sliding gesture to adjust brightness. You also get highlights, annotations, dictionary lookup, translation, text-to-speech, and a reading ruler for focus. Your library backs up to Dropbox or WebDAV, and reading positions sync between phone and tablet.