macOS is literally certified Unix. Apple still shells out for certification of their new releases, although I'm not sure what they're getting out of it given th

macOS is literally certified Unix. Apple still shells out for certification of their new releases, although I'm not sure what they're getting out of it given that macOS Server isn't a thing anymore. iOS is arguably a subset, but whether it's Unix-like or not is a philosophical question depending on how you define the minimal set of features that'd make it one. It's certainly not Unix-like from the end user perspective.