> and it comes up right away I'd be a bit afraid of this. Secure key derivation takes time. Remember, you want to be able to defend against people with a few

> and it comes up right away I'd be a bit afraid of this. Secure key derivation takes time. Remember, you want to be able to defend against people with a few GPUs or the ability to configure a cheap FPGA at least and the ability to build custom ASICs or employ a GPU botnet at worst. Taking ~5 seconds to derive your key securely on your phone is a near inevitability.