Bookends

Bookends is a macOS-native reference management application for collecting, annotating, organizing, and citing published information. It imports references and PDFs from sources such as PubMed, Google Scholar, JSTOR, arXiv, Google Books, and hundreds of institutional libraries, with a built-in PDF reader for markup and annotations that feed into an interactive note stream.

The app integrates with Microsoft Word, Mellel, and Nisus Writer Pro through Citation Inspectors and Floating Citations, and can scan manuscripts to produce formatted in-text citations, footnotes, and bibliographies using built-in or CSL styles. It supports iCloud sync, shared libraries, and a companion iOS app. Bookends also works with MCP-capable AI assistants to search references, read PDFs, add annotations, and generate bibliographies. Additional features include static and smart groups, hierarchical folders, tag clouds, and a browser extension for Safari, Chrome, and Firefox.

Bookends is aimed at researchers, academics, and writers who need to manage and cite literature. It requires macOS 10.13 or later and offers a free demo limited to 50 references; a registration code removes that limit and includes two years of updates.