Back in 2017, Apple deleted Touch ID and replaced it with Face ID. They didn’t keep both. They didn’t add Face ID to Touch ID. They went to the brave new world of biometrics and burned the old one down behind them.
But, the ashes had barely even settled before we started getting rumors of Touch ID’s return. It’s resurrection.
Not just in the new iPhone SE, which some people loved precisely because it had Touch ID, but in the flagship iPhones as well.
But, why would Apple kill it just to bring it back to life?
Touch ID
There were fingerprint scanners before Touch ID, of course, but none of them were as elegant, reliable, or secure as what Apple shipped with the iPhone 5s back in 2013.
That’s how Apple typically rolls. They wait. They watch. They identify problems. They prototype solutions. And, if and when they’re happy, they ship.
In Touch ID’s case, Apple went with a capacitive scanner instead of optical, so it was harder to fool with an image or prothetic. Apple converted the fingerprint data to math, transited it through a locked-down hardware channel, stored it in a secure element inside their custom 64-bit chipset, never let it get off-device, and only ever released a yes or no token through the system so individual apps couldn’t ignore the results.
This when, even years later, other vendors were caught leaving full fingerprint photos in world-readable directories on their phones and other fun stuff.
But, Touch ID wasn’t perfect. Far from it.
It didn’t work with gloves on or when your finger was excessively dry or wet, and if you cut or burned your finger, you’d basically have to re-register with a different finger.
And you had to physically touch the sensor for it to scan your fingerprint.
Also, everyone started doing good fingerprint scanners eventually, so where’s the flex in that?
Face ID
There were also face scanners before Face ID, of course, of course, but none of them were as elegant, reliable, or secure as what Apple shipped with the iPhone X back in 2017 either.
Apple didn’t scan the image of your face, they scanned the geometry, so the system couldn’t be fooled by images or even masks, converted it to math, and then used an adversarial neural network to not only compare readings and models, but evolve them over time and challenge them to reduce the chance of future spoofing.
This when other vendors were using scanners that could be fooled by photos and videos or wouldn’t work in low light, much less the dark.
But, surprise surprise, Face ID isn’t perfect either. Not at all.
It doesn’t work with face masks on or if the sun is blinding the camera, or you’re wearing sunglasses that block infra-red light.
And, you have to stick your face in front of the camera for it to scan you.
Also, other companies have now started shipping similar facial geometry sensors as well, so even that flex just isn’t quite so flexy any more.
In-Display
One of the reasons Apple switched from Touch ID to Face ID was because they wanted to get rid of the Home button that housed Touch ID and take the iPhone display corner-to-corner.
They could have left the Touch ID sensor there and made a notch for the bottom to match the one on top. Yeah, let that sink in for a hot second.
They could have moved Touch ID to the power button or to the back of the phone where the Apple logo is.
But, Apple didn’t like any of those options. So we got Face ID instead.
Other vendors, though, also wanted to go edge-to-edge but didn’t have Face ID as an option, so they started experimenting with something else — in-display finger print readers.
Now, sure, many of them already had their version of fingerprint scanners on the back or in the button, so they could have just left them there and gone about their full-screening. But Android phone makers want to flex too.
So, we first got optical in-display fingerprint scanners. Which had all the downsides of traditional optical scanners, including the need to light up the fingerprint to take a picture, and because they’re only taking a picture, they’re easier to fool with pictures and prosthetics. Though they try to use hardware and software countermeasures to mitigate against it.
Next, we got ultrasonic in-display fingerprint scanners. Those use sound waves to build a 3D model instead of a 2D image, making them sightly harder to spoof.
All of the early implementations were kind of terrible though. Slow. unreliable. Error prone.
But, over the last couple of years, they’ve gotten better and better.
Maybe, finally, good enough for Apple to copy?
iPhone 12
Back in January of this year, supply chain exfiltrator extraordinaire, Kuo Ming-Chi claimed that Apple is readying a full screen entry-level iPhone for early 2021 that would have Touch ID not in the display but in the power button. Presumably because a now-traditional capacitive fingerprint scanner in the button would be cheaper than either an in-display scanner or Face ID.
I’ll do a whole video on that phone, a full screen LCD iPhone that would sit somewhere between the classic design of the iPhone SE at $399 and the all-OLED iPhone 12 lineup starting at $649. So, make sure you hit subscribe if you haven’t already.
But this isn’t about that. No, because way back in August of 2019, Kuo also said that Apple was working on an ultra-sonic in-display fingerprint scanner for the iPhone 13 in 2021.
Kuo figured that thickness, sensing area, power efficiency, and lamination would all be solved enough by then for Apple to implement their own in-display patents.
Touch ID wouldn’t be seeking revenge or anything, and killing Face ID the way Face ID killed it, but rather it would be peace in our time — both Touch ID and Face ID living together in perfect harmony.
Mark Gurman and Debby Wu of Bloomberg followed up on that in September of 2019, saying Apple could ship the in-screen Touch ID system as soon as the iPhone 12 in 2020, but that it might slip to the iPhone 13 refresh in 2021 instead.
Also, that it would work on a large portion of the display, which is handy when you don’t have a precise, tactile, physical target like a home button to feel and hit, and that it would work in tandem with Face ID. Which could mean either or, for added convenience, or both, for added security.
Prior to Kuo and Bloomberg, way back in March 2019, Barclays analyst Blayne Curtis also reported that Apple would add ultra-sonic, in-display Touch ID to the 2020 iPhone.
But, given everything that’s gone on with closures in Chinese manufacturing centers and U.S. design and engineering centers this year, though, it seems less likely we’ll get Touch ID back this year and more likely we’ll get it pushed back to next.
Bummer, I know, because it doesn’t look like the need for masks and gloves is going anywhere any time soon.