i save documents in multiple formats: pdf and txt mainly.
i keep them reasonably sorted in specific folders, like 'bread', 'ferment', 'pasta', etc.
i sometimes tag the files with meta information, but that's not really necessary, since all **** is indexed, and if i want something i just do a folder wide search for certain ingredients or names of dishes, and all relevant results pops up neatly.
no need at all for keeping stuff in a certain app, or making any extra effort.
my folder system is pretty tidy though, so i can also look for things visually as well, like chapters and recipes in a cookbook.
the files are all on the cloud, so i can reach them from phone, computer, kitchen designated ipad, or whatever.
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