The reader that does not host the books
A free iOS reader that treats files, Calibre, and Gutenberg as one book, and does not host the rest.
- Category
- Consumer
- Who it is for
- Someone who already has files, a Calibre server, or a Gutenberg habit.
- Possible model
- Freemium
- Difficulty
- Hard
- Inspired by
- Yuedu · Yuedu
- Original launch
- Watch the launch · Oct 31, 2026
Difficulty is an editorial estimate of technical and operational complexity, not a score.
Startup idea analysis by Startup Ideas. Last reviewed Oct 31, 2026. How we read a launch.
The startup idea
Zrulin posted Yuedu on October 31. Books have no TMDB, so he built a reader like Emby. Public catalogs fill the home page. The same book from your files, a Calibre server, or Project Gutenberg is recognized as one. Pick a source and keep reading. The App Store listing is free. The minimum system is iOS 17. You can reorder the Explore home. Search covers the library, sources, OPDS, Calibre, public libraries, and Open Library. Official modules are public-domain books from Project Gutenberg and Aozora Bunko, plus book data from Open Library. Remote libraries are WebDAV, OPDS, and Calibre. Imports are EPUB, TXT, Markdown, PDF, and comic archives. The listing says the app does not include, recommend, host, or distribute copyrighted content sources. You are responsible for the files, feeds, and accounts you add. The post does not print that line. This page did not open a book.
The opportunity is one book page instead of three libraries. A smaller product is one title matched across two sources, and the copyright line on the same screen. A reader that hosts the catalogs as its own books is not this listing.
Do not host a copyrighted feed. Do not say the app is the bookstore.
The problem
The same book sits in three places, and a catalog is not a library.
Who would pay for this?
- Primary
- Someone who already has files, a Calibre server, or a Gutenberg habit.
- Secondary
- A person on iOS 17 who will not treat a catalog as a download.
- Early adopter
- One book, two sources, the copyright line visible.
How could it make money?
Possible models. Nothing here is a claim about what Yuedu charges.
- The listing is free.
- No account is required for a local file.
- The post does not name a price.
What would the MVP look like?
- One book matched across sources.
- Gutenberg and Open Library as modules.
- The does-not-host line.
- Import of an EPUB you already have.
How to validate the idea
- Ask five people whether a copyrighted catalog came with the app.
- If they say yes, the listing was missed.
- Do not ship a source the app claims not to host.
How to differentiate
- The book is the unit, not the source.
- Official modules are public domain.
- You bring the rest.
- Do not become a store.
Original product launch
This launch is inspiration and evidence that someone shipped, not a partnership. The idea above is our reading of the broader opportunity. Yuedu did not write it.
- Product
- Yuedu
- Source
- Yuedu
- Film
- Yuedu, the catalogs are not the books
- Posted
- Oct 31, 2026 · 0:47
Product that inspired this idea
Zrulin's post says books have no TMDB, so he built a reader like Emby. Public catalogs fill the home page. The same book from your files, a Calibre server, or Project Gutenberg is recognized as one. Pick a source and keep reading. The App Store listing is free, for iOS 17 or later. It imports EPUB, TXT, Markdown, PDF, and comic archives. Official modules are public-domain books from Project Gutenberg and Aozora Bunko, plus book data from Open Library. Remote libraries are WebDAV, OPDS, and Calibre. The listing says the app does not include, recommend, host, or distribute copyrighted content sources. You are responsible for the files and feeds you add. The post does not say that line. This page did not open a book.
Posted by @zruilin0417. Watch the original launch. No separate product site is listed unless the post itself is the source.
- ios
- reading
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