I use a YubiKey as well as iOS everywhere I use WebAuthn (currently only for 2FA). The only sites I don’t are the ones which don’t support more than 1 key. I

I use a YubiKey as well as iOS everywhere I use WebAuthn (currently only for 2FA). The only sites I don’t are the ones which don’t support more than 1 key. I haven’t come across any websites that restrict it to just iOS. I’m not even sure it would be easy (without fingerprinting), because the browser usually handles verification (and gives options for security key and iOS).