Kavita vs Ubooquity

Kavita and Ubooquity are both systems for organizing and reading comics and ebooks. They can be installed on a local server (or NAS) and provide access to the library via a web interface. Both programs allow to sort your collection by folders and metadata-parameters and support creation of multiple users (each can have their own library). Both systems are free and open-source.

But Kavita is more modern program with a user-friendly (desktop and mobile) interface and functionality for managing the library. It is created specifically for manga, light novels and web novels, has built-in tools for bookmarks and reading progress tracking. You can also customize reading profiles (i.e. the appearance of the reader) for different book types.

Ubooquity has a minimalist interface and only basic functionality. It's focused primarily on comics and PDF books. But it is easier to install, has lower requirements for computer resources and works more stably (does not require frequent updates). Among the unique features, I would note the built-in access to the library via OPDS