See Commonplace/Zettelkasten app
The method has been helpful but not ground-breaking for me over the last two years or so. I don’t pretend to be following it exactly, but it has led me to review linked notes on material I would have forgotten otherwise. I think it makes most sense if you’re doing ethnographic or historical research, esp. with grounded theory, with an interest in discourse, multivocality, that kind of thing – for a body of notes that are primarily factual, I don’t think it would offer a lot of advantages over more conventional search.