While Samsung and Huawei used Mobile World Congress (MWC) this week to show off their first folding smartphones — albeit behind glass several feet away from reporters' cameras — LG took a different approach.

With its new G8 ThinQ smartphone, LG left 5G and folding screens to one side, and instead focused on a new series of hand gestures called Air Motion. Using a time-of-flight sensor — used by facial recognition systems to map the shape of someone's face — the G8 is controlled with a wave of your hand.

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The technology identifies you, rather impressively, it must be said, from unique patterns of blood vessels in your hand, meaning you can unlock the handset by showing it a raised palm. But there are problems here. Air Motion is limited with what it can do, confined to taking hands-free screenshots, adjusting music volume, and opening a couple of applications.

LG began the launch event at MWC with a different phone, the new V50 ThinQ 5G. Apart from its unnecessarily long name, the handset looks like a good effort, and will be the firm's first 5G phone when it goes on sale in the next few months.

Meet the G8

But next came the LG G8 ThinQ, a successor to the G7 — LG's mainstream flagship smartphone. Unlike some of its rivals — like Samsung and OnePlus — LG is still using a conventional fingerprint reader, placed awkwardly on the back of the G8. There isn't an in-display reader for the G8, which is a disappointment as Samsung offers one (which happens to work very well) on the equally new Galaxy S10.

The G8 ThinQ is an attractive phone, but with few top-tier featuresGearBrain

LG has also stuck with the display notch form factor instead of switching to the subtler hole-punch front camera design of the Galaxy S10 and Honor View 20. At first glance, there is little to suggest the G8 comes from 2019 — a year when smartphone design is being shook up more than it has for some time.

What LG has done to make the G8 stand out, is actually quite smart — but only as a technical demonstration. The G8's time-of-flight sensor, which LG refers to as the Z camera on account of the axis it operates along, measures the time it takes infrared light to leave the phone, bounce off an object, and return to the sensor. With this data it can build an accurate 3D model of the world around it — or of your face — which can then be used as a form of biometric security, the same as Apple's Face ID.

This enables what LG calls 'palm vein authentication,' where the sensor reads the blood vessels patterns in the palm of your hand to identify you. The company claims this form of biometric authentication is far more secure than using a fingerprint, retina or 3D face scan, and that the odds of a stranger's palm unlocking your phone are one in a billion.

Air Motion gesture controls are limited and don't always work correctlyGearBrain

But in every other situation, raising a palm to unlock one's smartphone doesn't feel natural.

LG also suggested you could use the technology to unlock your phone while your hands are dirty — from cooking or baking, for example — but this seems like a pretty niche use case. Once unlocked, however, you'll still need to touch the screen to get things done. Currently, you could speak to the Google Assistant — to set a new cooking timer, for example, or make a call — without touching the phone either.

The company also said the system could unlock a phone while driving. But that surely still counts as interacting with the device — something widely considered illegal, or at the very least, dangerously distracting.

Trying Air Motion

Taking this technology and running with it even further, LG then introduced Air Motion. First, you open your hand and move your palm slowly away from the screen to get the phone's attention. An icon appears to show the phone is watching, which is meant to prompt you to close your hand a little, pointing your fingers at the display as if controlling a hand puppet.

Next, you can close your hand to take a screenshot, or point left or right to pick from a couple of applications. Another gesture lets you adjust the volume as if rotating a knob in thin air.

Gesture controls work best when asking an LG representative to do it for youGearBrain

When it works, Air Motion is...fine. It mostly operates as described and I was able to open Google Maps or turn up the music volume. But I really struggled to make it work reliably. Even after asking LG staff for a demonstration, I'd put the odds of the phone seeing my hand and doing as I wanted at around 40 percent. For me, it failed more than it succeeded.

It's my job to try these things out and persevere when they stumble, but I can't see an everyday smartphone buyer trying more than once or twice before giving up and forgetting about Air Motion entirely. "Minority Report" or "Iron Man," this is not.

Even if it worked flawlessly, opening apps in an instant, I'm still left wondering what the point of Air Motion is. After I've opened YouTube or Google Maps, I'm going to need to tap the screen anyway to find a video or type out an address. Perhaps a very quick and simple gesture to dismiss an incoming call could be helpful, while talking to someone in person and not wishing to appear distracted by my phone. But for now AirMotion requires a couple of seconds to engage with your hand before you can control it, and then there isn't much it can do.

Not to mention how weird it makes you look. The LG demonstration area at Mobile World Congress was full of journalists all gesturing at phones as if trying to make them levitate, or disarm Voldemort.

GearBrain

Air Motion verdict

I fear LG is making the mistakes Samsung made with the Galaxy S4 in 2013 — another phone packed to bursting point with more features than any user would deem necessary. On the S4, Air View allowed for photo browsing with a wave of the hand, and scrolled pages up and down as you moved your eyes. These features didn't work well and were quietly removed in time for the S6 two years later.

LG may need to run the same assessments, and ask of Air Motion is actually useful.

Does the feature save time? Does the technology make life easier? Is Air Motion convenient? And if the answer to these is no, is the use of it at least fun? Air Motion falls disappointingly short here. The technology needs to work quickly and flawlessly every single time, but it just doesn't.

It also feels like LG has, as with Apple and its Face ID system, locked itself into the 'display notch' design, necessary for the time-of-flight sensor. Yet Samsung's use of an in-display fingerprint reader let it skip right past any form of face recognition system, bypassing the notch design entirely, and opting for the more subtle hole-punch front camera. I've a feeling the notch design is going to date quickly, and that LG and Apple will be stuck with it for as long as they require space for their complex face, vein and hand-scanning systems.

One note: the LG phones at MWC were likely running beta software on pre-production hardware, so the experience could be improved before consumers get their hands on the G8 for themselves. Apple's FaceID didn't work too well after the iPhone X launch event, but improved by the time the smartphone went on sale. Even if Air Motion works as intended, the technology still feels like a solution to a problem that doesn't really exist.

The smartphone industry is moving quickly in 2019, innovating faster than it has for a while, with AI, 5G and folding screens accelerating into the mainstream. While I applaud LG for thinking outside the box, the company can't afford to become distracted by gimmicks. Otherwise, Samsung, Apple and Huawei will pull further away, while the likes of OnePlus, Honor, Oppo, Xiaomi and even a resurgent Nokia close in fast.