My iPhone SE, has touch ID, which works very well. But sometimes, maybe 5% of the time, it absolutely INSISTS on me typing in my passcode instead. When it asks for my passcode, I press cancel, and try touch ID again instead. Nope, it wants my passcode. Is there some sensible reason for this?
There are certain conditions where your phone will ask for your passcode:
There are certain conditions where your phone will ask for your passcode:
Thank you. OK, in my case, I guess it's the 8 hour delay. But, as far as I'm concerned, that isn't a sensible reason. Either it trusts touch ID or it doesn't! I have no idea why 8 hours makes your touch ID suspect. I guess Apple thinks that you turn into a gremlin after 8 hours, eh?
As far as I know, it's for both theft prevention and making sure you still know your iPhone password.
Additionally, the eight-hour timer only triggers when the iPhone or iPad hasn’t been unlocked with its passcode in the previous six days (So it won't happen EVERY time you don't unlock your iPhone for eight hours).
Well, no one in this user-to-user forum can answer a “why” question. It may be the way Touch ID is implemented. your fingerprint is stored in volatile memory. When you restart the phone it is retrieved from the “secure enclave” that requires the passcode to access. If you haven’t used the phone for a while it may be assumed that you have lost it, and the volatile memory (which contains other secure information) is cleared for security reasons.
And I like Bubba’s answer also.
Yes, that's reasonable that if you haven't opened up your phone in "a while" it might call for some backup proof, but the assumption that when I go to sleep, and don't open up my phone for 8 hours and one minute, my fingerprint is automatically considered "suspect" really makes no sense. 8 hours isn't really "a while". I guess I can see that, say, if I don't open my phone for a whole day or two, it might be considered odd.
Granted that no one in this user forum can answer why Apple chose to do this. Sure would be nice to get an explanation from Apple.
That must be correct. That the eight hour timer doesn't trigger unless six days go by. So Apple has also decreed that it doesn't trust your fingerprint after six days. Who knew that fingerprints had a lifetime?
So, um, why use Touch ID at all?
Well, it makes it convenient for the vast majority of times when you do unlock your iPhone :)
iPhone somtimes INSISTS on wanting my passcode
