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Orion ViewerReadEra
Free

Free and open source under the GPL.

 Free

Free to download and use without ads, according to the developer.

Android Android, iOS
  • Opens DjVu as well as PDF, XPS, CBZ and TIFF
  • Configurable tap zones and key bindings for page turning
  • Opens EPUB, MOBI, PDF, DjVu, Word, FB2 and comic files
  • Reads books directly from ZIP and RAR archives
  • Viewer only, with no PDF editing
  • Interface is functional rather than polished
  • Closed source
  • Mobile only, with no desktop version
Downloadable app Downloadable app
Open source Closed source
License: GPL-3.0-or-later License not stated
No account needed No account needed
Works offline Not stated if it works offline

Checked October 2, 2026

Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.