The most popular alternative is Zotero, which is both free and Open Source. If that doesn't suit you, our users have ranked 30 alternatives to BibDesk so hopefully you can find a suitable replacement. Other interesting BibDesk alternatives are Mendeley Reference Manager (Freemium), Qiqqa (Free, Open Source), JabRef (Free, Open Source) and ReadCube Papers (Paid).
- Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
- Academic software for organizing, sharing, and generating bibliographies for research papers.
- Qiqqa is a free research and reference manager. Search for, read and annotate your PDFs. Then review your work, write up and create bibliographies instantly.
- Bibliography reference manager. The native file format used by JabRef is BibTeX, the standard LaTeX bibliography format.
- Papers helps you collect and curate the research material that you're passionate about.
- Reference management software with support for collaboration, remote access, and automation.
- Organize your research papers in a Gmail-like web app, sync your PDFs to Google Drive and cite your references in Google Docs.
- Weava is a collaborative workplace for research offering an easy way to highlight, organize and collaborate on your research articles.
- Bookends is a commercial reference management software package for Mac OS X that is used to manage bibliographies and references when writing essays and articles.
- ZoteroBib is a free service to help people quickly create bibliographies without installing any software or creating an account.