The Open Publication Distribution System (OPDS) is an open standard that allows content servers to syndicate their publications, like e-books and comics, in a catalog format. This enables reader applications on devices like iPads and Android tablets to directly browse, download, and sync content from a remote library. I propose that Proton Drive implement OPDS support, allowing users to generate a secure OPDS feed for any specified folder.

This would function similarly to how many reader apps currently integrate with Dropbox or Google Drive. A user could simply right-click a folder (e.g., "My E-Books"), generate a unique OPDS URL with secure credentials, and plug it into their favorite OPDS-compatible reader app. Implementing this feature would be a significant strategic win. It would immediately close a major functional gap with competitors, making Proton Drive a feature-complete, private alternative for the large community of users who manage digital libraries. This transforms the service from a simple file vault into an active, integrated part of a user's daily life, dramatically increasing ecosystem stickiness.