The purpose of the fingerprint is basically to be an extra button the device. You could get 95% of the security benefit of this with a special new button on th

The purpose of the fingerprint is basically to be an extra button the device. You could get 95% of the security benefit of this with a special new button on the iphone ("login") and a normal passcode. The value is having credentials stored in the secure element of the phone, or encrypted under keys in the secure element (which is a standard keystore API thing since ios5), with a set of APIs for apps to access them and present a UI action to the user. It's no different from the windows SAK (ctrl-alt-del) or the Mac "administrative user" dialog box.