You pull your phone out of your pocket and casually place your thumb on the screen. You feel THAT buzz as your phone refuses entry. Without investing too much focus, you slide your thumb to re-orient, but before you properly place your thumb down again, you feel the “bad buzz”. Now, fully invested with your visual and tactile attention, you prepare for attempt number three…

Best case scenario, you get into your phone and realize the notification you received really wasn’t worth this effort. Worst case, you have to put in your pin or password, and the notification was even LESS worth this effort.

We had it so good. What happened?

Optical fingerprint sensors make me really cranky. Ultrasonic fingerprint sensors are a LITTLE bit better. There are literally only TWO phones (from the same manufacturer) where I enjoy the in-display experience.

We used to have these great pieces of hardware, dedicated spaces, with tactile landmarks, that we could press with a finger and thumb. In-display LOOKS cooler. In-display sensors LOOK high tech, but they’re poor replacements for the sensors we used to get.

Ergonomics

I love Star Trek, specifically classic Trek through Deep Space Nine. The one thing that always bugged me about the Next Gen years though, the reliance on touch screens. You’re piloting the flagship of a futuristic space navy, and in tense situations, you have to perfectly land on tiny icons and keys, which change layout over a completely featureless smooth flat glass display.

It LOOKS high tech, but it’s incredibly impractical.

When we study how people drive their cars, we’re building more data on interactions. Increasingly, buttons are a better solution for attention and completing tasks WHILE operating a motor vehicle.

Likewise, unlocking your phone has always been faster, easier, and requires less attention when we use dedicated sensors on the front, side, or rear.

Take an OLD Samsung, Pixel, or LG, and those tactile sensors were easy to consistently find with VERY little muscle memory training. You can consistently “no look” open your phone. The device is in a ready-to-use state before it’s up to your face.

People CAN get BETTER at using in-display after really training their muscle memory, but using numerous phones for review, I can never replicate the experience of a good power button sensor while using a phone with an in-display sensor.

Performance

At their best, in-display sensors are still slower and less consistent than dedicated sensors.

Again, a deliberate focus on unlocking an Ultrasonic sensor is faster than an optical sensor, but neither approach the consistency and security of dedicated sensors.

Samsung spent TWO YEARS struggling with in-screen sensors. From the Galaxy S10, through the Note 10, S20, and Note 20, Samsung sensors were clumsy and often insecure. Reviewers glossed over slow unlocks and situations where you could unlock the phones with unregistered fingers.

TWO YEARS and four major phone releases, Samsung only “fixed” the issue by using a newer larger sensor from Qualcomm on the S21. Software updates helped improve those older phones, but the main issue was hardware.

This is compounded by the fact that we use (and abuse) our screens with daily use. An optical sensor struggles if there are more streaks and smudges on the screen. The same screen you interact with for EVERYTHING you do on the phone.

If you’re phone has a rear mounted fingerprint sensor, and you crack the bottom of your screen, you can still unlock your phone with little worry of slicing your thumb open.

The frustrating aspect of “aesthetic technology”, it doesn’t do anything better than the tech it replaces.

The best we can hope for is a gimmicky “after action” on a display fingerprint sensor. Hold to unlock, then hold longer to activate a short cut. The main use isn’t better, and the additional benefit isn’t worth the extra effort in many cases.

We used to have nice click-y home buttons with extra functionality, and I miss being able to slide my notification shade from rear sensors.

Alternatives and Improvements

“But Juan, You said there were two phones with in-display fingerprint sensors you DID like? Doesn’t that render this whole rant moot?”

The vivo X80 Pro and the iQOO 9 Pro have these bleeding edge MAX sensors which are significantly larger than anything we’ve seen before. This is a leap in surface area from Qualcomm, and it’s the first time I feel an in-display sensor STARTS to approach the casual use of a dedicated sensor.

When I don’t have to be as exact with my unlock movement, and the sensor is genuinely accurate enough to unlock almost anywhere I place my thumb, I’m a much happier camper.

The increase in sensor size also adds extra security and short cut features. You can literally put a shortcut IN the window of the unlock to go directly to a specific app.

The sensor is broad enough that you can secure files with a double fingerprint scan. You can pick ANY two fingers to lock files, and the sensor is big enough to scan them at the same time. We’ve never seen features like this before, and it finally feels like there’s some technological progress over dedicated sensors.

And only TWO phones currently have this sensor.

I hope this in-display will be more common over the coming years, but it’s an EXPENSIVE piece of tech, which really only makes sense currently on EXPENSIVE phones.

In Your FACE!

I’ve also complained about face unlock, which similarly, seems to add extra steps to what was previously a more seamless activity. I genuinely try to only handle my phone with some purpose. I use a smartwatch as a gatekeeper for notifications and replies.

If I pick up my phone, there needs to be a reason for me to interact with it, and anything that slows that interaction down is going to be annoying. I detailed some of this crankiness in the video below.

Sometimes it’s OK to go back…

I have an incredible collection of phones sitting in front of me while I write this.

Older phones, newer phones, inexpensive, premium tier, and I’m encouraged that we can still find some options with dedicated hardware unlock. Productivity devices like the Moto Edge+ and Surface Duos, photography focused hardware like Sony XPERIAs, and mid-ranger fare from Xiaomi and Poco.

Handling the recent Poco M4 and the top-of-the-line Xiaomi 12S Ultra, the Poco is so much more reliable than the Xiaomi when I want to open and USE the phone.

I ran an unlock challenge earlier in the year.

How fast can you lock and unlock a phone ten times? No great surprise that an inexpensive Poco is demonstrably faster in this kind of race than ANY in-display.

Also no great surprise that folks who owned more expensive phones cried foul in my finding a feature which was demonstrably poorer than the solution on a “cheap” phone.

I’m honestly not trying to “yuck” anyone’s “yum”. I want people to like the phones they own, and I want people to find the PERFECT fit gadget for their needs. TOO many people have the wrong fit solution because they simply bought what was popular.

It’s OK to still like your phone DESPITE an inferior bio-metric security feature, but let’s not pretend the experience is on equal footing with tactile dedicated sensors.

My main criticism faces an industry that seems to have given up on innovation and evolution. There’s still plenty we can do with traditional slate phones to make them better products. There are still areas of disruption where consumers can find more bang for their gadget buck.

The in-display fingerprint sensor is a perfect example of change for aesthetic sake. It’s less reliable. It’s often less secure. It’s more finnicky with use and with screen protectors. It’s less ergonomic. It’s slower and more deliberate to use. It increases complexity around the display, often making repairs more complicated.

The only “win” for the in-display sensor is “it looks kinda cool”.

It’s OK to like “It looks neat”, but we shouldn’t pretend it’s a better technology. We could have a better technology instead.