Facebook handles apps that don't support 2factor pretty well. Your first login will be rejected but you'll be messaged the 6 digit code to login with as your "password".
> If you could mimic another person's fingerprint or DNA at will, you could do some seriously evil stuff. MD5 is clearly compromised, and SHA-1 is not looking too great these days.
You cannot "mimic" another person's fingerprint with MD5. Currently you can only "create" two people with the same fingerprints.
This might sound the same but consider the case where you want to replace someone's notepad.exe with an evil notepad.exe (and make sure that it has the same MD5 so they don't notice). Currently, no attack exists to do that.