I was a long-time user of Papers3.app but it’s no longer being developed, and I’m not super optimistic about ReadCube.app, which came in to replace Papers3.
I have used Mendeley throughout grad school, but would love to look into alternatives now that that chapters is closed and I dont need the same citations anymore. Mendeley worked for what i needed, just saving sources and formatting citations for manuscripts and my thesis.
I’m a big fan of Zotero! It works well with all of the other major citation managers, and that makes life a lot easier when it comes to writing papers across labs where not everyone has the same software. It doesn’t have a ton of bells and whistles, but is still fantastic.
Mendeley definitely has my vote. It is not perfect, but I like saving, reading, highlighting articles on different devices. I also like the creation of project dedicated folders, add and search by key words, add notes and share papers with my colleagues. Finally, it does a pretty good job in inserting and formatting citations and bibliography in Word.