Comment by simpaticoder

Why don't banks use PKI? It doesn't have to be in the users face. It might be that your app generates a keypair on startup and sends the public key to the bank server, and the bank server sends you a public key, and you talk to each other with a shared secret. Maybe even you have to go in physically to the bank with your device to set it up and attest the legitimacy of your private key. Personally I'd really love that.