Story

For me, the system keychain (OS X/iOS) is good enough.

As for replacing passwords with something else: I haven't seen a convincing replacement yet and I can't think of one myself either.

One problem is, that passwords work for a huge variety of use cases.
Example: A random web page wants me to sign in for no apparent reason. I can just make up a new password and use a temporary email address. I wouldn't want to use any authentication method - like a smart card or something - that was tied to my identity.