Face ID, after someone has used your phone

[ivanwi11iams]

On 5th November, I purchased an iPhone X. And since then, Face ID has worked virtually 90+% of the time.

Oddly, today, someone wanted to see my iPhone X (first person I've left even look/play with it), and now, Face ID is intermittent.

From recollection, I could have sworn I'd read an article or post about this happening to someone else.
So, the question is, do I need to reset the Face ID, or how do I get Face ID back to being over 90% accurate?

Thanks in advance
Ivan

 

[Newtons Apple]

Letting your friend use your X for a while should not make any difference with FaceID. They could not have accessed and re-done the face ID without a passcode.

Maybe you should try re-doing Face ID and see if that helps.

 

[eagleglen]

When he handed it back to you, did you have to type in your passcode? It might have scanned his face and when you reentered in the passcode, it added his face metrics to yours. Another possibility, is to just restart the device. Re-scanning your face is the definitive fix, barring some hardware glitch, but that really shouldn't be necessary.

 

[QquegChristian]

This is exactly what I’ve been wondering. If my wife and I can/are making FaceID less effective by using each other’s phones? We know each others’ passcodes. I ask my wife to respond to texts or change the directions or music on my phone while I’m driving all the time.

I do know that my wife’s FaceID was very hit or miss after first set up. She registered her face, then I spent an hour setting up the rest of her phone for her, using her passcode many times. By the time I hand it back, FaceID was noticeably slower on her phone than mine, failing a few times as well. I had her redo the setup for it and it works perfectly.

 

[ivanwi11iams]

I actually gave the person my device locked. But, if I recall, after a few minutes they wanted to see something on the screen, so I unlocked it (Face ID), and then handed them the device.

Thanks for the input. I'll reset Face ID.

 

[C DM]

I actually gave the person my device locked. But, if I recall, after a few minutes they wanted to see something on the screen, so I unlocked it (Face ID), and then handed them the device.

Thanks for the input. I'll reset Face ID.

Sounds like that shouldn't have affected anything.

 

[dk001]

Hopefully it is not FaceID that itself is the issue. Basic common behavior like this, especially amongst couples / families should not affect it. If it does Apple has problem. Rather, FaceID has a problem.

 

[D.T.]

This is exactly what I’ve been wondering. If my wife and I can/are making FaceID less effective by using each other’s phones? We know each others’ passcodes. I ask my wife to respond to texts or change the directions or music on my phone while I’m driving all the time.

Not unless you look enough like to fall into the "range of uncertainty".

Basically there's two behaviors when it misses:

1) it's a complete miss, and entering the passcode doesn't affect the stored facial data

2) it's a miss, but close enough where the system not confirm, but thinks it might be you. When you enter your passcode after this result, you're actually training the system, basically saying, "Yes, this is me".

The assumption is behavior 2 requires a pretty close match (just shy of a 100% confirmed, which if course would result in a positive authentication).

 

[hush17]

FaceID stopped working for me the other day. It didn't recognise me even in scenarios that I consider optimal for a successful scan. I thought the hardware failed until I rebooted the device and everything went back to normal. I blame iOS 11.