The best replacement for bibdesk is jabref.

The best alternatives to bibdesk are rated as following:
★★★★★  jabref
★★★★★  zotero
★★★★  papers
★★★  bibtex
★★★  mendeley
★  sente
  bookends

Your alternative for bibdesk is not listed? Suggest!
Speaking about bibdesk, one probably shouldn't forget about texshop.

Other search terms related to bibdesk and their ratings are:
★★★★★ texshop
★★ google scholar
★★ biblatex
You have in mind a companion for bibdesk and it is not yet here? Propose!



Google Trends

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bibdesk
jabref
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