Compare software

Koodo Reader vs ッツ Ebook Reader: catalog facts
Koodo Reader	ッツ Ebook Reader
Free Free and open source under the AGPL-3.0.	Free Free to use, with the source code published on GitHub.
Windows, macOS, Linux, Android, iOS, Web	Web, Self-hosted
Over fifteen formats including EPUB, PDF, MOBI, AZW3, comic archives and DOCX Syncs through storage you already control rather than a vendor cloud	Works with Yomitan and similar dictionary extensions Runs in the browser with nothing to install
It reads DRM-free files only; books bought from a store with DRM will not open Sync depends on whatever storage you configure, so the setup is on you	Focused on Japanese reading rather than general ebook management Dictionary lookups depend on a separately installed browser extension
Downloadable app, Web application	Web application, Self-hosted
Open source	Open source
License: AGPL-3.0	License not stated
No account needed	Not stated if an account is needed
Works offline	Works offline
Official website Full listing and sources Checked September 20, 2026	Official website Full listing and sources Checked October 1, 2026

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