Google Pixel 4 Face Unlock feature: How will it work, comparison with Apple’s Face ID

Google Pixel 4 Face Unlock feature: How will it work, comparison with Apple’s Face ID

Google has confirmed that the Pixel 4 series will come with a Face Unlock feature. Here's how Face Unlock feature will work on the Pixel 4 smartphone thanks to the new Soli radar chip

Google Pixel, Pixel 4, Pixel 4 Face unlock, pixel 4 Face unlock feature, Pixel 4 launch date, Pixel 4 specifications, Pixel 4 features
Google Pixel 4 will finally have a Face Unlock feature, and here’s how it will work. (Image source: Google)

Google has confirmed that the Pixel 4 series will indeed come with a brand new Face Unlock feature. The previous Pixel phones did not offer Face Unlock and it might appear that Google is late to the party, given that this kind of solution was already being offered by various companies. But Google Pixel 4’s Face Unlock packs a different technique, which will make it stand out compared to what’s present in the market.

How will Face Unlock on Google Pixel 4 work?

Google has confirmed that the Pixel 4’s Face Unlock feature will rely on a number of sensors for its accuracy. The front of the phone will have a Face Unlock Dot Projector, Face Unlock IR camera and Face Unlock Flood Illuminator.

The front of the Pixel 4 has another Face Unlock IR camera on the top bezel along with the regular front facing camera, ambient light/proximity sensor, the audio port and Soli radar chip. From the pictures, it does not look like Pixel 4 has a notch. Based on the image that Google has shared, the Soli radar chip is also a part of the Face Unlock feature.

While Google is yet to go into the details of how the Face Unlock feature will work, given the kind of sensors it packs, Face Unlock should work under most lighting conditions and thanks to the Soli radar chip, the feature will be fast when it comes to unlocking the phone.


The Pixel 4’s Face Unlock feature will work accurately even in completely darkness given Google is relying on two IR cameras. Just like Apple’s Face Unlock, Google is using an array of sensors from the Dot Projector, Flood Illuminator as well. All of these will be capable of capturing of a lot of data before it unlocks the device.

But what is different with Pixel 4’s Face Unlock?

The biggest difference with the Pixel 4 is that Face Unlock feature will work in any orientation or angle. As Google wrote in the blog post: “As you reach for Pixel 4, Soli proactively turns on the face unlock sensors, recognising that you may want to unlock your phone. If the face unlock sensors and algorithms recognize you, the phone will open as you pick it up, all in one motion.”

Google Pixel, Pixel 4, Pixel 4 Face unlock, pixel 4 Face unlock feature, Pixel 4 launch date, Pixel 4 specifications, Pixel 4 features
Google Pixel 4 as seen from the back. (Image source: Google)

The difference here is the Soli radar chip, which can sense the smallest of motion and thus detect human intent. So unlike an iPhone XS, you don’t have to hold the phone in front of your face to unlock it. Google’s Pixel 4 will recognise you are picking it up, and open the device should the right face be detected. So the device will unlock, without you having to hold it in front every single time.

Google also says the Face Unlock feature will work even if you are holding the device upside down, which is not possible on other phones just yet. Face Unlock on Pixel 4 can be used for secure payments and app authentication as well, which other devices also offer. The key differentiating factor in the Pixel 4 will be how seamlessly and quickly this Face Unlock will work.

What’s this about Google paying $5 to test Pixel 4’s Face Unlock?

Zdnet had first reported that Google employees were roaming in select US cities offering users $5 Amazon gift cards or Starbucks cards in exchange for testing out the new face unlock feature.

According to the ZdNet report, one Google employee approached a reporter’s friend in New York saying, “‘I work for Google and we’re collecting data to improve the next generation of facial recognition phone unlocking.” Google later confirmed that it was indeed carrying out this field research, according to The Verge.

How does Apple Face ID work in comparison to the Pixel 4’s Face Unlock? 

In case of  Apple’s Face ID, the company is only using one Infrared camera, while Google will be relying on two of these, which are placed on either side. It is not clear why Google has used two of these cameras.

On the iPhone X, iPhone XS, iPhone XR, Face ID uses the what Apple calls the TrueDepth camera system in the front, the Secure Enclave and the Neural Engine on the processor to lock/unlock the phone. It has been reported that the new iPhones in 2019 will have an upgraded Face ID system.

Apple is also using a Dot projector, which relies on more than 30,000 invisible dots, which are projected onto the user’s face to build a unique facial map. The Infrared camera reads the dot pattern and captures an infrared image, which is sent to the Secure Enclave in the A12 or A11 Bionic chip on the iPhone XS or iPhone X respectively to confirm the match.

The Flood illuminator relies on invisible infrared light to help identify the face even in the dark. As noted, the Pixel 4 is relying on all of these features as well.

In Apple’s case, Face ID uses on machine learning to recognise changes in appearance from glasses to a hat to makeup and continues to work in all such instances. Google will also be using machine learning and neural networks for its Face Unlock feature.


In Apple’s case, all of the processing for Face ID is done on-device and not in the cloud to “protect user privacy.” Apple also says that the feature only works when the user looks at the device. It also claims that Face ID cannot be fooled by photos of the user or even sophisticated 3D masks.