Comprehensive Tech Review: Face ID

Face ID is something I never thought I’d use much. As someone who has always had an iPhone that doesn’t get upgraded much, Face ID or Touch ID technology was never something I used consistently. On earlier iPhone models, using Face ID or Touch ID is much more inconsistent and glitchy in comparison to the models that have been currently released. I will be conducting my tech review on Face ID tech with a iPhone 12 Pro Max model.

Let’s start with the different interactions on the iPhone 12. First off, unlocking the device. Unlocking the device may seem like a simple task, but it is something that needs to be done smoothly and without any errors for users to actually use face ID technology.

Unlocking the iPhone

iPhone 12 Pro Max steps on unlocking a phone w/Face ID

  • Phone is locked, screen is black.
In this video, it shows the Face ID interaction on an iPhone 12 Pro Max.

When Face ID Fails

There are many different circumstances where face ID may fail. When this interaction fails, you are led through the interaction by unlocking your phone using your passcode.

  1. The padlock logo shakes when the interaction fails and the user is prompted to “swipe up to unlock.”
Trying to unlock my Phone using Face ID with a Facemask on.
After failing the Face ID interaction, you are led to enter your passcode manually.

Unlocking your phone in different situations

There are several situations where face ID might not work correctly, so I will outline those situations!

Bad lighting

In my experience, I have never had too much of a problem with using my face ID in different lighting situations. Obviously if it’s pitch dark or your camera sensor is being hit with direct sunlight, it might be glitchy, but in most lighting situations, it should perform fine.

Wearing a Facemask

When wearing a facemask, it is almost impossible to unlock your phone using face ID. Although Apple has made several strides to make it easier to unlock your phone if the face ID interaction fails (like last spring the company released software that made it easier to avoid using Face ID while wearing a mask, by showing the iPhone’s passcode screen after the first time Face ID fails), it is still impossible to unlock your phone with only half your face showing.

Standing too far away or too close to Phone

The distance between you and your phone is very important for face ID. In my experience with testing to unlocking my phone using face ID, your face can be around 2–2.5 feet away with it still functioning correctly. I tested this by having my face around 3–4 feet away from my phone and slowly moving my face forward until it unlocks.

Opening a Banking App using face ID

Using Face ID to sign into my Deserve account
When Face ID fails

In most situations, banking apps do a great job with using face ID tech. When successful, the interaction is almost flawless and takes less than 5 seconds. When unsuccessful, it waits around 3–5 seconds for your face to be in view, gives the users a pop up with “Face Not Recognized” and you have 2 choices (as seen in the second picture above.) If you press “Try Face ID Again,” it will scan your face again and either sign into the app, or bring you to the third image above. If the face ID still fails a second time, you then enter your password unless you want to exit the app.

Heuristic Analysis

In this section, I will be reviewing the face ID interactions of unlocking a phone for everyday use and signing into a banking app from the standpoint of Nielsen’s 10 Heuristics.

#1: Visibility of system status - In terms of generally using face ID to unlock your phone, the padlock logo interaction is something subtle, but very important. It’s something that if you took away, the user would have no idea what is going on and they wouldn’t know what state their phone would be in.

The padlock design is also a great example of Nielsen’s heuristic #2: Match between system and the real world, as unlocking and locking padlocks follow real-world conventions and flow seamlessly from the real world to the screen.

Likewise, the interaction where the padlock shakes and then says, “swipe up to unlock” after failing the face ID is also an example of Nielsen’s heuristic #1: Visibility of system status. The shake is a more subtle interaction as it shows that the phone is not able to be unlocked. The message that follows — “swipe up to unlock” is a great reminder for users to remind them how to complete that interaction and avoid being lost, especially if they are new to the iPhones interface.

I do think that for a new user some of the interactions are a bit vague and could be confusing to new iPhone users. For example, an interaction that sometimes happens when unlocking your phone is that you’re presented with this screen (img below) This screen occurs when the Face ID is a failure, but there is no instructions or directions on how to “escape” from this screen if you don’t want to use Face ID. Obviously for someone who is used to the iPhone 12 mechanics, you would naturally swipe up because swiping up is essentially the replacement for the home button. But overall, adding the few words “swipe up to unlock” next to the padlock on this screen would fix this problem.

Deserve Banking App

In terms of the interaction with the Deserve banking app again, the heuristic #1: Visibility of system status is shown during the process of the Face ID interaction when it’s a success. It also gives the user pop up notifications when the Face ID fails, but I’ll go into that in a bit. I really like how you can see the progression of signing in for the banking app and how fast the interaction is (it’s only about 2 seconds) where you see the face ID logo change (In the image below is the progression)

Signing into the Deserve app using Face ID

In the first logo image it shows the beginning of where you’re first putting your face into view. The second logo animation where this blue swirl is animating is where the app is loading and processing your face. The third and final step is the checkmark that symbolizes the process being completed and finished!

In terms of error status’s, the “Face Not Recognized” pop-up is a great example of heuristic #9: Help users recognize, diagnose, and recover from errors. This error message is expressed in plain language, indicates the problem and constructively suggests a solution to the problem. It also provides a Cancel button, which is an example of heuristic #3: User control and freedom because it shows a clear way to exit the current interaction.

Accessibility Review

In this section, I will be reviewing Face ID interactions from an accessibility standpoint.

While unlocking an iPhone with face ID or even signing into a banking app, both of these interactions require the look-to-unlock feature, requiring the user to have an active gaze. This feature is called “Require Attention for Face ID” on the iPhone and is a setting that can be turned off and on depending on your needs as a user. In an 2017 article, The iPhone X: What does Face ID mean for Accessibility? The company that published this piece believed that,

“even when disabling these features Face ID still isn’t natural. Many visually impaired users tend to use headphones for audio feedback while holding their phone in a comfortable position i.e. around waist level, rather than holding it up to their face to unlock.”

I would definitely agree that a visually impaired person may have difficulty navigating face ID, so it could be beneficial to create an easier way for visually impaired people to incorporate audio or sounds that correspond to the interaction of unlocking a cellphone.

Another interesting accessibility feature that I had no idea existed as well was the “Haptic on successful authentication” feature. The description for this feature is: Play a haptic when Face ID successfully unlocks iPhone, authorizes Apple Pay, or verifies iTunes and App Store purchases. Haptics is also the use of technology that stimulates the senses of touch and motion. In this case, every time Face ID successfully unlock the iPhone, a small vibration will occur. This will notify users will any visual impairments that the interaction was a success.

Inclusivity Review

In this section, I will be reviewing Face ID interactions from an inclusivity point of view.

Face ID should be designed for everyone, no matter their skin color, eye shape, face shape, etc. In a news article by TNW, they speculate, “Apple claims that it used one billion images to train the algorithm — ideally nullifying any questions of diversity in the database.” Keeping this in mind, “There might have been a billion images, but what percentage were Caucasian vs. Chinese, Black or Indian?” I think this is an important idea to keep in mind that as a Caucasian user, my experience using face ID may be different than if a Black user were to use face ID. Ideally, we want every user experience to be flawless that’s why inputting as much diverse data into face ID algorithms and testing with all users in mind is so important.

In general, I believe the Face ID interactions using a iPhone 12 are generally inclusive, but there is an underlying racial inequality in the racial recognition algorithms across many different tech giants. In a research article by Harvard University, they report that. “A growing body of research exposes divergent error rates across demographic groups, with the poorest accuracy consistently found in subjects who are female, Black, and 18–30 years old.”

“Figure 1: Auditing five face recognition technologies. The Gender Shades project revealed discrepancies in the classification accuracy of face recognition technologies for different skin tones and sexes. These algorithms consistently demonstrated the poorest accuracy for darker-skinned females and the highest for lighter-skinned males.”


Face ID is a great emerging technology, and has proven its usefulness through different avenues. I think for any designer designing for face ID, keeping the user informed on the status of the interaction is a must, but also keeping the design simple and easy to use. For the most part, face ID is a great interaction when it is successful. When the interaction fails it gets a bit more difficult, so really pushing heuristic #9: Help users recognize, diagnose, and recover from errors is something face ID designers should emphasize while they are designing.

I also think in terms of accessibility and inclusivity, problems like making face ID more accessibly to the visually impaired and addressing the underlying racial inequality in the racial recognition algorithms are so important because all users should be able to successfully unlock their phone using face ID!