Foam is free, open source, and extremely extensible to suit your personal workflow. You own the information you create with Foam, and you’re free to share it, and collaborate on it with anyone you want.
AnalyzeMyRepo.com is a free tool to learn about the adoption, contributions, diversity, and governance of any GitHub repo. It crunches data from 150k+ repositories daily and provides valuable insights with charts, checklists, and written summaries.