I can seem to reply to derefr, but to echo his comment, this will be a safety measure in the same way that Apple's TouchID is a security measure.
We know that a fingerprint is a bad password.It can't be changed, you leave copies everywhere, authentication is based on an approximation, etc. Strong, frequently changed passwords would be much better. But is it significantly better than the security on most people's phones: a 4 digit passcode, or none at all.
We know that a fingerprint is a bad password.It can't be changed, you leave copies everywhere, authentication is based on an approximation, etc. Strong, frequently changed passwords would be much better. But is it significantly better than the security on most people's phones: a 4 digit passcode, or none at all.