The best android app for book readers on mobile devices is this one called moon + reader.
It has features that no other app has could theme and ☆ Support epub, pdf, mobi, chm, cbr, cbz, umd, fb2, txt, html, rar, zip or OPDS, key features:
✔ Full visual options: line space, font scale, bold, italic, shadow, justified alignment, alpha colors, fading edge etc.
✔ 10+ themes embedded, includes Day & Night mode switcher.
✔ Various types of paging: touch screen, volume keys or even camera, search or back keys.
✔ 24 customized operations (screen click, swipe gesture, hardware keys), apply to 15 customized events: search, bookmark, themes, navigation, font size and more.
✔ 5 auto-scroll modes: rolling blind mode; by pixel, by line or by page. Real-time speed control.
✔ Adjust the brightness by sliding your finger along the left edge of the screen, gesture commands supported.
✔ Intelligent paragraph; indent paragraph; trim unwanted blank spaces options.
✔ “Keep your eyes health” options for long-time reading.
✔ Real page turning effect with customized speed/color/transparent; 5 page flip animations;
✔ My Bookshelf design: Favorites, Downloads, Authors, Tags; self bookcover, search, import supported.
✔ Justified text alignment, hyphenation mode supported.
✔ Dual page mode for landscape screen.
✔ Support all four screen orientations.
✔ EPUB3 multimedia content support (video and audio)
✔ Backup/Restore options to cloud via DropBox, sync reading positions between phones and tablets.
✔ Highlight, Annotation, Dictionary (Offline or Online, support ColorDict, GoldenDict, Fora, ABBYY Lingvo, etc.), Translation, Share functions all in this ebook reader.
-Localized in 40 languages.
Download link https://play.google.com/store/apps/details?id=com.flyersoft.moonreader
For Apple users Official Books App is still Best.
