Docspell is described as 'personal document organizer. You'll need a scanner to convert your papers into files. Docspell can then assist in organizing the resulting mess 😉' and is an app in the Office & Productivity category. There are more than 100 alternatives to Docspell for a variety of platforms, including Windows, Mac, Linux, Android and Online / Web-based. The best alternative is Evernote, which is free. Other great apps like Docspell are CherryTree (Free, Open Source), Zim (Free, Open Source), NoteLedge - Creative Notebook (Paid) and TagSpaces (Freemium, Open Source).
Polar is a powerful desktop app for managing all your web content, books, and notes. Polar keeps all your content in one place, supports tagging, annotation, highlighting and keeps track of your reading progress.
Nuclino is the easiest way to organize and share knowledge in teams. Create real-time collaborative documents and connect them instantly like a wiki. Use the tree, board, and graph view to explore and organize your knowledge visually.