calibre - Ebook manager, viewer & converter
Solid Explorer - Solid Explorer is a powerful Android file manager featuring access to most popular cloud storages, root access and easy extensibility.
FBReader - FBReader is an e-book reader for various platforms. Features:
Amaze File Manager - Free and open-source Android file manager with no ads.
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Total Commander - A Shareware file manager for Windows® 95/98/ME/NT/2000/XP/Vista/7, and Windows® 3.1.