I used Zotero and their Chrome Extension when I was reading research papers. It automatically formatted citations, allowed me to add annotations and also locall

I used Zotero and their Chrome Extension when I was reading research papers. It automatically formatted citations, allowed me to add annotations and also locally saved any PDFs so I can access it quickly. You can also send different types of links such as videos, PDFs articles directly to Zotero. I'd highly recommend it!