Managify - Create & organize all your documents in a single platform.
Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
Files Board - Organize & manage your documents, photos and videos
Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.
Sismics Docs - Lightweight full-featured document management system 📁
JabRef - Graphical Java application for managing bibtex (. bib) databases.JabRef · JabRef Help · JabRef | Blog · OpenOffice/LibreOffice .