Stolen device protection-- what happens if biometrics fail?

[oldguy79]

I think I've read quite a bit about this but haven't seen the answer to this. SDP turns phone authorization on its head. Without it, the passcode is the principal auth mechanism. But with it, what is the "source of truth"? It seems biometrics is, and I don't trust biometrics. And you need the passcode to initially set up biometrics, so the reference seems circular. I don't understand the math.

I had an iPhone 6+ with Touch ID for about 5 years. I tried dozens of times to set up TouchID and it would only work for a few minutes, or maybe a bit longer-- but if I washed my hands or didn't wash my hands for a while it would fail. I remember calling Apple Support several times and going through all their remedies, but no. Last year I got an M2 Macbook Air and it works a little better -- it will remember my fingerprint for about a day but that's it.

I've always assumed it's because I'm an old guy and my fingerprints are maybe worn down or wrinkled or whatever.

My experience with Face ID has been better. I've had my FaceID phone for about four years and can't remember if I've ever had a problem with it. Maybe once or twice. But because of my experience with TouchID I can't really trust it. My fingers are not the only part getting more wrinkles.

So what happens if you turn SDP on and biometrics fail? My partner has seen the news articles about SDP and thinks it's a good idea but she hasn't used FaceID on her new phone. She doesn't trust it for different reasons than I (mainly just an overwhelm with technology in general).

 

[Morac]

If Significant locations are enabled and the phone learns your home location, which can take a few weeks, then you can just turn off SDP while home with a passcode.

Otherwise you’ll have to put your phone in recovery mode and do a restore with a Mac or PC to disable SDP.

A note about Touch ID, it uses the resistance of your finger prints not technically the texture. Older people tend to have poorer circulation in their hands, especially when it’s cold which can cause TouchID to not work as well. Adding extra fingers or the same finger twice can help with that.

FaceID is more reliable as it uses a 3D LiDAR image of your face which isn’t impacted by things like cold. It also has more area to match which is why something like growing a beard doesn’t confuse it.

 

[oldguy79]

Thanks. Very useful information.

 

[P_Watt]

I've always assumed it's because I'm an old guy and my fingerprints are maybe worn down or wrinkled or whatever.

Me too (72) but there are 4 prints you can set up. SE 2022 touchID is pretty reliable and Morac should have reassured you.

 

[Alfilde]

...Touch ID, it uses the resistance of your finger prints not technically the texture.

After renovating my window frames, which involved hand sanding, my iPhone stopped recognising my fingerprints. If it’s true that Touch ID relies on fingerprint resistance rather than texture, is there a chance that my iPhone might recognise them again once my fingertips have recovered from the work? For example, my iPad has started recognising my fingerprints occasionally – not every time, but more and more often. However, my iPhone still doesn’t recognise them.

In other words, is there still hope that I can disable SDP on my own phone?

 

[Morac]

After renovating my window frames, which involved hand sanding, my iPhone stopped recognising my fingerprints. If it’s true that Touch ID relies on fingerprint resistance rather than texture, is there a chance that my iPhone might recognise them again once my fingertips have recovered from the work? For example, my iPad has started recognising my fingerprints occasionally – not every time, but more and more often. However, my iPhone still doesn’t recognise them.

In other words, is there still hope that I can disable SDP on my own phone?

Texture will impact resistant so if you sanded off your fingerprints then it’s not surprising that Touch ID stopped working. Theoretically once your fingertips recover Touch ID should start working, though there’s no guarantee. It depends on how much damage you did. In the future it might be a good idea to wear gloves when sanding. That or add a finger to Touch ID that you are less likely to use like a pinky or something.

If you can’t disable SDP, you can always backup the phone to a computer or iCloud, wipe the phone and restore the backup. That’s time consuming but will work.

 

[Alfilde]

I did, in fact, wear gloves, but the damage to my fingertips isn't due to superficial injuries to the epidermis. It’s more related to swelling in the underlying dermis. I have Raynaud's Syndrome, which causes poor circulation in the peripheral microvessels, leading not only to cold hands or feet but also to numbness. However, I usually regain sensation after a while as the edema subsides.

And yes, I know that I could back up and then restore the phone. But the thing is, I want to save my Signal messages, which are not transferred to iCloud in the backup.
And as if the problem with disabling SDP wasn't enough, I also have Signal saved in Hidden apps, which again requires my fingerprint to open….. 🙄

 

[Ruggy]

As you say, you have to enter a passcode, before setting up the biometrics and if the biometrics fail, then you will be prompted to enter your password.
If you have forgotten the passcode or enter a wrong passcode too many times, it gives you a time-out which gets longer every time you do it.
If you have completely forgotten your passcode and as long as you use icloud and have your apple ID, then you can erase the phone using Find my. Then you go into icloud on the net and unlock it again with your apple id and set it up or restore it , the phone being registered to your apple id.
If you need to restore something not included in iCloud then you will need another back up of that but then, that's always true for if you smash your phone or have it stolen.

 

[Alfilde]

”… you have to enter a passcode, before setting up the biometrics and if the biometrics fail, then you will be prompted to enter your password…”

Knowing my passcode doesn't resolve the issue. When I attempt to disable the SDP, register a new fingerprint, or switch from 'always' to 'familiar location,' I end up stuck in a frustrating loop: after entering the passcode, I'm asked for a fingerprint, which fails, and then I'm prompted for the passcode again, only to be asked for the fingerprint once more, which still doesn’t work.

I've also tried removing the phone from 'Find My' and re-adding it to my iCloud account. Unfortunately, that didn't solve the issue either. And as I’ve mentioned before, I don’t want to reset the phone because I don’t want to lose my Signal app messages.

I must say, with all due respect, Apple has certainly succeeded in making it extremely difficult for unauthorised eyes to access the content on an iPhone. It's so secure that I can't even access my own data

 

[Morac]

I did, in fact, wear gloves, but the damage to my fingertips isn't due to superficial injuries to the epidermis. It’s more related to swelling in the underlying dermis. I have Raynaud's Syndrome, which causes poor circulation in the peripheral microvessels, leading not only to cold hands or feet but also to numbness. However, I usually regain sensation after a while as the edema subsides.

Unfortunately you may be SOL. TouchID doesn’t work for some people. For example it doesn’t work for my dad during winter. Honestly if you had prior issues with TouchID not working, you probably should not have enabled Stolen Device protect and set it to always use TouchID even in known locations. If you had allowed known locations you could have used your passcode at home.

You could try warming your hands and see if touchID starts working, but your only bet might be to transfer your signal messages to another phone, do a restore and then transfer them back.

 

[Adora]

Since I had to wait "forever" to log out of "find my" for restoring an iPhone as new, I disabled this completely.

 

[960design]

I think I've read quite a bit about this but haven't seen the answer to this. SDP turns phone authorization on its head. Without it, the passcode is the principal auth mechanism. But with it, what is the "source of truth"? It seems biometrics is, and I don't trust biometrics. And you need the passcode to initially set up biometrics, so the reference seems circular. I don't understand the math.

I had an iPhone 6+ with Touch ID for about 5 years. I tried dozens of times to set up TouchID and it would only work for a few minutes, or maybe a bit longer-- but if I washed my hands or didn't wash my hands for a while it would fail. I remember calling Apple Support several times and going through all their remedies, but no. Last year I got an M2 Macbook Air and it works a little better -- it will remember my fingerprint for about a day but that's it.

I've always assumed it's because I'm an old guy and my fingerprints are maybe worn down or wrinkled or whatever.

My experience with Face ID has been better. I've had my FaceID phone for about four years and can't remember if I've ever had a problem with it. Maybe once or twice. But because of my experience with TouchID I can't really trust it. My fingers are not the only part getting more wrinkles.

So what happens if you turn SDP on and biometrics fail? My partner has seen the news articles about SDP and thinks it's a good idea but she hasn't used FaceID on her new phone. She doesn't trust it for different reasons than I (mainly just an overwhelm with technology in general).

Biometrics is never the answer for security.
Finger print? What if the person has no hands.
Eye scan? What if the person has no eyes.
Finger print hacked... how does the original person change their finger prints?
et cetera....

Biometrics are a cool feature in Hollywood cartoons, but not for true security.
Biometrics may be used as a 'convenience' feature.

 

[960design]

A note about Touch ID, it uses the resistance of your finger prints not technically the texture. Older people tend to have poorer circulation in their hands, especially when it’s cold which can cause TouchID to not work as well. Adding extra fingers or the same finger twice can help with that.

It has been known to fail with lizard people and aliens as well.

 

[Morac]

Biometrics is never the answer for security.

Actually biometrics is replacing passwords for security. That’s the whole concept of Passkeys.

 

[emembee]

I must say, with all due respect, Apple has certainly succeeded in making it extremely difficult for unauthorised eyes to access the content on an iPhone. It's so secure that I can't even access my own data

I agree, it locked me out of my iPad and I had to wipe it, I won't be using SDP again.

 

[Morac]

I agree, it locked me out of my iPad and I had to wipe it, I won't be using SDP again.

SDP isn’t even available on the iPad.

 

[emembee]

Sorry, my mistake, I meant my iPhone SE which is a spare so I put on SDP but had to wipe to get it up and running again.