Citation Managers

Zotero is a free and open source, easy-to-use tool to help you collect, organize, annotate, cite, and share research. Save high-quality publication data from websites, journal articles, newspapers, and more, or retrieve publication data for PDFs. 

A built-in PDF reader lets you mark up PDFs and extract cited quotations and comments directly into notes or word processor documents. It can automatically add publication data by DOI or ISBN and find open-access PDFs when you don't have access to a paper. If you open a paywalled page in your browser, Zotero can automatically redirect you through Saybrook's proxy so you can access the PDF if available. 

Free - storage limit is 300MB

Upgrade:

• 2GB of storage: $20/year
• 6GB of storage: $60/year
• Unlimited storage: $120/year

Free version is suitable for many users

Access is through a mobile app, desktop client, a web client, and a bookmarklet for many browsers

You can create groups that allow you to share citations and files with other people

Can annotate and search full-text PDFs

Can save and cite web pages; saves snapshot of entire web page

Word processor plug-ins available for Microsoft Word, LibreOffice, and Google Docs

Quick capture feature with no sign-in

Allows you to easily cite with a click of a button directly from the source that you are referencing when writing 

Large projects require purchase of additional storage

Limited de-duping

Fewer reference styles than other citation managers

Zotero doesn't work well if you open an external PDF from a website as it cannot pull author information correctly from a PDF source

Some limitations to sharing

No direct export from databases