Forget in-display, this is the golden age of side-mounted fingerprint scanners

In just a few years, in-display fingerprint scanners have gone from the exciting cutting edge to self-evident. By comparison, button-mounted security just isn’t seen as that exciting, but we’re actually living through the golden age of technology. Spent time with the Asus Zenfone 9 and Sony Xperia 1 IV, I am now convinced that side-mounted fingerprint scanners are the superior implementation, at least for now. Let me explain.

For example, they are faster. Miles faster. Not only in terms of access, but also registration. The Zenfone 9’s scanner is so fast that I can’t physically remove my finger fast enough to make it fail. We rated the Poco F4s side-mounted scanner also very high in this regard. Sony’s Xperia 1 IV isn’t quite as punchy, but it’s still sharper and more accurate than so many of the in-display scanners I’ve used over the years.

Compared to the icy Google Pixel 6, the experience is night and day. In-display variants are notoriously finicky with wet (and dry) fingers and screen protectors, which is not the case for physical scanners.

There are also other benefits. Scanners hidden in the power button are equally discreet, but you also always know where they are. The variety in the display is clearly well hidden, but guessing exactly where the reader is when the screen is off can be a problem. The scan areas are often also quite small, you have to be precise to avoid re-scanning; in comparison, the power button is effortless to locate. Likewise cheap optical scanner types (I’m knocking you out again, Pixel) cast a blinding light as you read in the dark. Nobody likes their retinas being scorched to check WhatsApp.

On good authority: How bad is the Pixel 6’s fingerprint scanner anyway?

Button-based fingerprint scanners could also be smarter. Asus’ Zenfone 9, for example, features assignable gestures to quickly launch apps, drop the notification shade, activate Google Assistant, and more. A double tap, hold or quick swipe up or down increases quick access to your most used features without cluttering up your lock or home screen. It’s the kind of simple and obvious feature that adds tons of value incredibly easily, yet seems to have eluded flagship manufacturers who are too busy chasing the latest tech fad.

Fingerprint gestures aren’t new, of course. Clumsy gestures were popular back when phones still had some semblance of a bezel to house chin-based scanners and when manufacturers thought the best place to put them was the back. With the original Pixel, for example, you can drop the notification shade with a swipe across the back of the phone. But embedding them into the existing power button is brilliantly elegant and could theoretically be available on any single smartphone regardless of design identity.

This is not to say that there are no excellent in-display fingerprint scanners on the market. The Vivo X80 Pros 3D ultrasonic sensor (pictured below) stands out as the best current example. With a huge scanning area, one-touch fingerprint registration and shortcuts for launching apps, it’s intuitive, smart and clearly a step above what’s currently on the market, even in the premium flagship space.

Also see: This is an in-display fingerprint reader done right

While the X80 Pro offers an exciting glimpse into the future of in-display technology, it remains an outlier in the world of in-display technology. Hopefully we’ll see more phones with this scanner configuration in the near future, but the cost, internal space considerations, and display support may remain a barrier to entry for some time to come. Especially when it comes to the mainstream.

Not every button fingerprint scanner is great, of course, but the modern era seems to have nailed the formula. Whether you’re spending ultra-premium with the $1,600 Xperia 1 IV or budget cash for the $399 Poco F4, a fast, reliable and secure experience is at your fingertips. Meanwhile, the Zenfone 9 convinced me that fingerprint gestures are so convenient yet so simple that every smartphone should have them. If that means getting rid of in-display fingerprint scanners for a few years until technology catches up, so be it. It’s just a better marriage of form and function.