Using client-side script to restrict access is a big no from a security stand point. From what I have read this library is intended to interact with third party services rather than for access. E.g. pulling in photos, contacts etc
Portability is one of my main concerns as I use a variety of platforms e.g. Linux at home, Windows at work and Android on the go. I would also be a little hesitant to trust a hosted solution. SuperGenPass (www.supergenpass.com) seemed like a nice solution but I am concerned about what happens when I need to change password.
Does Yubikey have a solution for Android? They seem right up my street.