Apps similar to Grimmory include calibre, which is free and open source. Other options are GCstar, Calibre-Web, Tellico and Thorium Reader. There's no shortage of Ebook Libraries like Grimmory, with more than 25 alternatives for Windows, Mac, Linux, Android and self-hosting.
Free e-book manager with features including library management, format conversion, syncing to devices, internet-independent operation, built-in viewer, news download as e-books, text-to-speech, privacy focus, extensible plugins, and no registration or tracking.
India
Desktop application to manage of various types of collections (books, comics, films, TV shows, music, games, wines, stamp, coins, etc...).
Calibre-Web is a web app providing a clean interface for browsing, reading and downloading eBooks using an existing calibre database.
Germany
EU
Tellico is a software application for organizing your collections. It provides default templates for books, bibliographies, videos, music, video games, coins, stamps, trading cards, comic books, and wines. You can also create your own custom collection of anything you like!
United States
Thorium Reader is a free, open source multi-language EPUB reader for Windows 10, MacOS and Linux. It's privacy aware and highly accessible for visually impaired and dyslexic people.
FranceEU
Citadel helps you manage your ebook libraries. It provides a simple, user-friendly interface to add new books to your library or update book metadata like titles, authors, and tags, all while remaining compatible with Calibre.
MyLists: organize and track series, anime, movies, games, books and manga, all in one place.
FranceEU
The most powerful and easy-to-use Book Organizer
Alfa Ebooks Manager is a free program that allows to organize your electronic and paper books in single e-Library.
Russia
Take control of your digital library. BookHeaven is a tiny self-hosted ecosystem that helps you manage and read your e-books in a very convenient way.
SpainEU
Easily catalog your movies, books, music, comics and games. Work on your phone, tablet or computer and sync data between them.
NetherlandsEU
myCollections is the perfect tool to catalog Applications, Books, Games, Music, Movies, TV show or Adult contents, into the same and unique tool.
GermanyEU
Numento is a elegant collection software fully customizable that will let you freely choose your method of management. Manage your library (Books,CD, DVD, comic books, games), your coins, your stamps, your postcard, etc.
FranceEU
