> There's a lot of stuff that depends on the secure element - in fact the phone would be quite useless without it.
Disclaimer: I don't own an iPhone with Touch ID.
However, it seems to me that the phone should still work if you logged on with your PIN instead of with TouchID. It should therefore be as useful as most phones that didn't have TouchID in the first place (which happens to be all my Android and iOS smartphones).
Correct. In fact, a passcode is always required the first time after you reboot your phone. The passcode secures the Secure Element, which contains the fingerprint data used by Touch ID.
Disclaimer: I don't own an iPhone with Touch ID.
However, it seems to me that the phone should still work if you logged on with your PIN instead of with TouchID. It should therefore be as useful as most phones that didn't have TouchID in the first place (which happens to be all my Android and iOS smartphones).