A PasswordCard is a credit card-sized card you keep in your wallet, which lets you pick very secure passwords for all your websites, without having to remember them! You just keep them with you, and even if your wallet does get stolen, the thief will still not know your actual passwords.
A very cute idea, well implemented.
Your PasswordCard has a unique grid of random letters and digits on it. The rows have different colors, and the columns different symbols. All you do is remember a combination of a symbol and a color, and then read the letters and digits from there. It couldn’t be simpler!
A chain is only as strong as its weakest link. It’s far safer to pick secure passwords and write them down, than it is to remember simple and easy to guess passwords. You already protect your wallet very well, and even if it does get stolen the thief will still not know which of the many thousands of possibilities on the card is your password.
Master passwords is the one thing i would find it somewhat useful. But even then, when you encrypt something with a password you would want a passphrase instead for more entropy. So even here it falls short.
Use OnlyKey for master passwords