KOReader

KOReader is a must-have app if you're looking for a comprehensive multi-format document reader that consumes barely any resources and prioritizes performance over appearance. By eliminating all distractions from the screen, KOReader makes for a simple but functional reader that delivers exactly what it promises.

KOReader is compatible with most popular text formats, including EPUB, PDF, DjVu, XPS, CBZ, FB2, PDB, TXT, HTML, RTF, CHM, DOC, MOBI, and ZIP files.

Best of all, using KOReader couldn't be easier. After opening the app, you can explore the folders on your smartphone to find the files you want to access. Simply tap on the files in question for a full view.

KOReader includes plenty of features to help you tailor your experience, including night mode, zooming capabilities, and important shortcuts.