KOReader

KOReader is a free document reader built for e-ink screens: one app that opens PDF, EPUB, DjVu, FB2, Mobi, comic archives and more, with a reading experience tuned for e-ink, no animations, adjustable contrast, fast page turns, rather than ported straight from a phone or tablet app.

It runs directly on the e-reader's own hardware (Kindle, Kobo, PocketBook, Cervantes or reMarkable, as well as Android and Linux), replacing or sitting alongside the device's stock reading software, and can be extended with plugins. It also reaches out, when asked, to outside services such as Calibre, Wallabag, Wikipedia and OPDS catalogs over the device's own network connection.