Works great, they even have ones with USB on one side and Lightning on the other for older iPhones.
replyWorks just fine, you have to get the one with NFC
replyYou can also plug them in to the USB-C port, works just fine.
replySome functionality is not supported via USB-C. Namely HMAC Challenge does not work via usb-c but will work via lighting port.
replyiPhones are a lost cause.
replyPasskeys on my iPhone works awesome.
replyToo bad for Yubikey. I don't need them any more.