Paperpile vs Zotero

Paperpile is a reference manager for collecting, organizing and writing with research papers. It can import references, extract PDF metadata, organize libraries with folders and labels, detect duplicates, repair metadata and search collections. Plans include unlimited storage for research PDFs. Citation support includes more than 10,000 styles, with plugins for Google Docs and Microsoft Word. Shared folders and libraries, access permissions, and collaborative PDF annotations and citations support group work. The Android and iOS apps sync with the web library and support highlights, notes and drawn annotations. Users can also search 150 million articles across sources including PubMed, arXiv and CrossRef, and save PDFs with one tap. Integrations include Google Drive sync, Overleaf, browser extensions, and academic databases and publishers. Regular costs $4.15 a month and Expert costs $5.75 a month, with all plans billed annually; a 30-day trial is available. New sign-ups are currently available on Chrome, while Safari and Firefox access is in beta.

Zotero is an open-source tool for collecting, organizing, annotating, citing and sharing research. Its browser Connector can identify research items during browsing and save them to a library. Collections, keyword tags and saved searches help organize material, while a PDF reader and note editor support working with documents. Zotero supports over 9,000 citation styles and integrates with Microsoft Word, LibreOffice and Google Docs. The desktop app stores research locally by default; syncing is optional. Zotero Storage can sync PDFs, images, web snapshots and other files across devices, with access through an online library. Libraries can be shared with any number of people at no cost, and groups support shared collections. The free plan includes 300 MB of storage; paid storage starts at $20/year for 2 GB. Zotero says synced data is encrypted in transit and newly created accounts' data is encrypted at rest with AES-256. The data server is in the United States. The data server software can be run locally, though Zotero says self-hosting is technically challenging and unsupported. Most support takes place in public forums.