iPhone Face ID: Must Eyes Be Open to Unlock?

Understanding Face ID's Core Requirement: Attention Awareness

When you use Face ID to unlock your iPhone, a common question arises: do your eyes actually need to be open? The direct answer is that Face ID is designed to work best and most securely when your eyes are open and looking at the device. This isn't just a random design choice; it's a critical security feature called 'Attention Awareness'.

Apple engineered Face ID with sophisticated sensors that can detect if your attention is directed towards your iPhone. This means it checks for signs of awareness, such as your eyes being open and focused on the screen. The primary purpose of this feature is to prevent unauthorized access. For instance, if your iPhone is on a table and someone tries to unlock it by holding it up to your face while you're asleep or distracted, Attention Awareness would prevent it from unlocking. It ensures that the unlock is intentional and that you are actively participating in the authentication process.

The TrueDepth camera system, which powers Face ID, captures a detailed depth map of your face. This system can recognize subtle cues associated with looking directly at the device. By requiring your gaze, Face ID adds a robust layer of security, distinguishing between someone using your phone while you're present but not actively engaging with it, and someone genuinely intending to unlock it. Therefore, while Face ID can technically recognize your face with eyes closed, its most secure and intended operation relies on them being open and directed at the iPhone.

The Science Behind Attention Awareness

Apple's Attention Awareness feature is built upon the capabilities of the TrueDepth camera system. This system goes beyond simple facial recognition; it analyzes specific indicators of engagement. When your iPhone is unlocked, Attention Awareness looks for the presence of your eyes and whether they are directed towards the screen. This process is automated and happens in the background as part of the unlock sequence.

The system is trained to identify the characteristic patterns of a face that is looking forward. If it detects that your eyes are closed, or if they are looking away from the device, it will not proceed with the unlock, even if it recognizes your facial features. This makes it significantly harder for someone to unlock your phone without your active consent. It’s a proactive measure against opportunistic theft or unauthorized access, ensuring that your personal data remains protected even when the phone is physically near you but not in use.

This technology is a sophisticated fusion of hardware and software, leveraging machine learning to adapt and improve its accuracy. The goal is to provide a seamless yet secure authentication experience. For the majority of users, this means that for Face ID to work as intended, conscious engagement by looking at the device is necessary.

The primary security function of Face ID relies on its ability to detect your directed attention.

How Attention Awareness Enhances Security

Attention Awareness fundamentally strengthens the security posture of Face ID. Without it, a malicious actor could potentially unlock your iPhone if they could somehow position it in front of your face while you were asleep or incapacitated. By requiring that your eyes are open and looking at the device, Face ID ensures that unlocking is an intentional act.

This feature distinguishes between passive recognition and active authentication. Passive recognition might identify you are present, but active authentication confirms you are deliberately using the device. This added layer of verification is crucial for protecting sensitive information stored on your iPhone, such as financial data, personal messages, and health records. It’s a subtle but powerful deterrent against unauthorized access.

Consider the scenario where your phone is laid on a desk, and someone casually picks it up. If Face ID unlocked without requiring your attention, they could potentially access your data. Attention Awareness prevents this by requiring you to look at the screen. This makes the unlock process contingent on your direct, conscious interaction, thereby safeguarding your device even in environments where it might be handled by others briefly.

Configuring Face ID: Eyes Open and Attention Aware

When you first set up Face ID on your iPhone, you are guided through a process that involves scanning your face. During this setup, the iPhone prompts you to move your head in a circular motion to capture a comprehensive 3D map of your facial features. Crucially, this process requires your eyes to be open and looking towards the TrueDepth camera.

After the initial setup, Face ID is typically configured by default to use Attention Awareness. This means it will expect your eyes to be open and looking at the device for it to unlock. You can verify and adjust these settings within the iPhone's Settings app. Navigating to Face ID & Passcode allows you to see the current configuration and make changes if necessary.

Steps to Manage Face ID Settings

To ensure your Face ID is set up correctly, or to adjust its behavior, follow these steps:

1. Open the Settings app on your iPhone.
2. Scroll down and tap on Face ID & Passcode.
3. You may be prompted to enter your iPhone's passcode to proceed.
4. Look for the option labeled Attention Awareness Features.
5. Ensure this toggle is switched On. This is the setting that requires your eyes to be open and looking at the iPhone for Face ID to work.

If you wish to disable this specific security feature, you can switch off 'Attention Awareness Features'. However, it is strongly recommended to keep this setting enabled for maximum security. Disabling it means Face ID will unlock your iPhone even if your eyes are closed or looking away, which significantly reduces its protection against unauthorized access.

For instance, if you have a medical condition that prevents you from looking directly at the phone, or if you find the feature inconvenient in specific, rare circumstances, you have the option to disable it. However, understand the security implications before doing so.

The 'Require Attention for Face ID' Setting

Within the 'Face ID & Passcode' settings, the 'Require Attention for Face ID' option (or similar wording depending on iOS version, often grouped under 'Attention Awareness Features') is the key control. When enabled, Face ID will only unlock your device if it detects that you are looking at it. This check involves verifying that your eyes are open and directed towards the screen.

This setting is vital for distinguishing between intentional unlocking and passive recognition. It ensures that your iPhone doesn't unlock accidentally or if someone tries to trick it. For example, if you fall asleep with your phone nearby, or if someone tries to unlock it by holding it to your sleeping face, the 'Require Attention' feature will prevent the unlock because it won't detect your gaze. This proactive security measure is a cornerstone of Face ID's robust design.

Keeping 'Require Attention for Face ID' enabled is crucial for preventing unauthorized unlocking.

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When Might You Consider Disabling Attention Awareness?

While disabling Attention Awareness is generally not advised due to the security it provides, there might be very specific, edge-case scenarios where a user might consider it. These could include individuals with certain medical conditions that make direct eye contact difficult or impossible, or perhaps users in environments where they frequently need to unlock their phone rapidly without direct eye contact, and are willing to accept the reduced security. However, for the vast majority of users, the security benefits far outweigh any minor inconvenience.

Troubleshooting Face ID: When Eyes Aren't Recognized

Even with Attention Awareness enabled, sometimes Face ID might seem to not recognize your face, or you might wonder if it's working correctly. The most common reason Face ID fails to unlock your iPhone is simply that your eyes are not open and directed at the device as the Attention Awareness feature requires. However, other factors can also contribute to recognition issues.

If Face ID isn't unlocking your iPhone, the first thing to check is whether you are looking directly at the screen with your eyes open. A quick glance can be enough, but if your eyes are closed, looking away, or if the phone isn't positioned properly in front of your face, the unlock will fail. This is by design to maintain security. Sometimes, environmental factors like very bright sunlight or complete darkness can also affect the TrueDepth camera's performance, although Face ID is designed to work in a wide range of lighting conditions.

Other common culprits include obstructions like sunglasses that block infrared sensors, or a facial covering like a mask (though newer iOS versions support Face ID with masks, it may require specific setup or not work in all scenarios). If Face ID repeatedly fails, the iPhone will eventually prompt you to enter your passcode, which is the fallback authentication method.

Common Reasons for Face ID Failure

When Face ID struggles to unlock your iPhone, consider these common reasons:

• Eyes Closed or Looking Away: The most direct answer to 'do your eyes have to be open to unlock iPhone' is yes, for secure operation with Attention Awareness enabled. If your eyes are closed or you aren't looking at the device, it won't unlock.
• Obstructions: Sunglasses, scarves, or even certain hats that obscure a significant portion of your face, especially your eyes and forehead, can interfere with the TrueDepth camera's ability to scan your face accurately.
• Lighting Conditions: While Face ID is robust, extreme lighting conditions—either excessively bright glare or near-total darkness—can sometimes impact its performance.
• Camera Lens Obstruction: Ensure the TrueDepth camera system (located at the top of the iPhone's screen) is not blocked by dirt, a screen protector, or a case.
• Facial Changes: Significant changes to your appearance, such as growing a beard, wearing makeup for the first time, or having a new piercing, can sometimes affect recognition. Adding an Alternate Appearance in Face ID settings can help.
• Device Position: The iPhone needs to be within the optimal range of the TrueDepth camera, typically between 10 to 20 inches away from your face.

Regularly check that the TrueDepth camera area is clean and unobstructed.

What to Do When Face ID Isn't Working

If Face ID is consistently failing, follow these troubleshooting steps:

1. Verify Attention Awareness: Ensure you are looking directly at the iPhone with your eyes open. If you suspect Attention Awareness is the issue, temporarily disable it in Settings to test if Face ID unlocks.
2. Clean the Camera: Gently wipe the front-facing camera area (which houses the TrueDepth system) with a soft, lint-free cloth.
3. Check for Obstructions: Remove any sunglasses or facial coverings that might be interfering.
4. Reset Face ID: Go to Settings > Face ID & Passcode, enter your passcode, and tap 'Reset Face ID'. Then, set it up again, following the on-screen prompts carefully. Ensure your eyes are open and you are looking at the iPhone during setup.
5. Add an Alternate Appearance: If you've made significant changes to your appearance (e.g., growing a beard, wearing glasses), consider setting up an 'Alternate Appearance' in Face ID settings.
6. Restart Your iPhone: Sometimes, a simple restart can resolve software glitches affecting Face ID.
7. Ensure Software is Updated: Make sure your iPhone is running the latest version of iOS, as updates often include performance improvements and bug fixes for features like Face ID.

If none of these steps resolve the issue, there might be a hardware problem with the TrueDepth camera system, and you may need to contact Apple Support for further assistance.

Face ID vs. Touch ID: A Comparative Look

When discussing biometric authentication on iPhones, Face ID is the current standard, but for a long time, Touch ID was the primary method. Both systems serve the same fundamental purpose: to securely unlock your device and authorize purchases, but they operate on different principles and require different user interactions.

Face ID uses advanced 3D mapping of your face, capturing depth and detail to create a unique profile. It relies on the TrueDepth camera system and, as we've established, requires your attention – meaning your eyes generally need to be open and looking at the phone for it to unlock. This makes it highly secure against spoofing attempts, especially with Attention Awareness enabled. It offers a hands-free unlocking experience once set up, provided you're looking at the device.

Touch ID, on the other hand, uses a fingerprint sensor to authenticate users. It typically requires you to place your finger on a specific sensor (which was integrated into the Home button on older models or built into the power button on newer ones like the iPhone SE). While it doesn't require your eyes to be open, it does require physical contact with the sensor. The security level of Touch ID is also very high, but it's vulnerable to physical fingerprint duplication, though this is exceptionally difficult to achieve.

Key Differences in Authentication Methods

The primary distinction lies in the biometric data used and the interaction required:

• Biometric Data: Face ID uses a detailed 3D map of your face, including depth and unique facial landmarks. Touch ID uses the unique patterns of your fingerprints.
• Sensor Technology: Face ID utilizes the TrueDepth camera system (infrared dot projector, infrared camera, flood illuminator). Touch ID uses a capacitive or ultrasonic fingerprint sensor.
• Required User Action: Face ID requires you to look at the iPhone with eyes open (when Attention Awareness is on). Touch ID requires you to place a registered finger on the sensor.
• Environmental Factors: Face ID can be affected by extreme lighting or obstructions like masks/sunglasses (though some exceptions exist). Touch ID can be affected by wet, dirty, or injured fingers.
• Device Placement: Face ID works best within a certain range and angle, and requires you to orient the phone towards your face. Touch ID requires direct physical contact with the sensor.

The hands-free nature of Face ID is a significant convenience factor for many users.

When Touch ID Might Be Preferred

While Face ID is now standard on flagship iPhones, Touch ID still has its place, particularly on models like the iPhone SE. There are specific scenarios where Touch ID might be considered more convenient or practical:

• Mask Usage: While Apple has introduced Face ID with a mask option for newer iOS versions, it's an opt-in feature that requires more setup and may not be as universally reliable as Touch ID for those who wear masks frequently.
• Discreet Unlocking: In situations where you need to unlock your phone quickly without drawing attention or looking directly at it, a Touch ID sensor (like the one on the power button of an iPhone SE) can be more discreet.
• Fingerprint Scan Reliability: For individuals whose facial features might change drastically or frequently (e.g., due to certain professions or medical conditions), registering multiple fingerprints might be perceived as more straightforward than re-training Face ID.
• Device Orientation: Touch ID is less sensitive to how the device is held. You can unlock it while it's lying flat on a table or in awkward positions where holding it up to your face for Face ID would be inconvenient.

Ultimately, both technologies offer excellent security. The choice between them, or the preference for one over the other, often comes down to user experience, specific model availability, and individual use cases.

Alternative Authentication Methods for iPhones

While Face ID and Touch ID are the primary biometric security features on iPhones, Apple provides a fundamental and universally accessible method for device security: the passcode. This alphanumeric or numeric code is the bedrock of iPhone security and serves as a crucial fallback when biometric authentication fails or is unavailable.

Every iPhone user must set up a passcode upon initial setup. This passcode is essential for unlocking the device, authorizing App Store purchases, and accessing certain security settings. It's designed to be robust, especially with longer, more complex combinations. While it doesn't offer the speed of biometrics, its strength lies in its universal application and its ability to function regardless of environmental conditions or physical obstructions that might affect Face ID or Touch ID.

Beyond the standard passcode, other methods might be relevant in specific contexts, such as using an Apple Watch to unlock your iPhone or Mac, or for enterprise environments that might use Mobile Device Management (MDM) profiles for additional security layers, though these don't typically replace the core unlock mechanism.

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The Role of the Passcode

The passcode is the most fundamental security layer for your iPhone. It's a sequence of numbers or characters that only you know, providing a direct authentication method. When Face ID or Touch ID is unavailable, disabled, or fails multiple times, your iPhone will prompt you to enter your passcode. This ensures that your device remains secure even if its biometric sensors encounter an issue or are temporarily unusable.

Apple encourages users to set a strong passcode. While a 4-digit passcode is the default, you can opt for a 6-digit code or even a custom alphanumeric passcode for enhanced security. The strength of your passcode directly impacts how vulnerable your device is to brute-force attacks. A weak or easily guessable passcode can undermine the security provided by even the most advanced biometric systems.

Your passcode is the ultimate failsafe for iPhone security.

When Biometrics Fail: The Passcode Fallback

Biometric authentication, whether Face ID or Touch ID, is designed for convenience and speed. However, there are situations where it might not be the best or only option:

• After Restart: Following an iPhone restart, you are always required to enter your passcode first to re-enable Face ID or Touch ID. This is a security measure to prevent unauthorized access if the device is lost or stolen and then rebooted.
• Failed Attempts: If Face ID or Touch ID fails multiple consecutive times (typically five), the iPhone will lock you out and require your passcode. This prevents brute-force attacks against your biometrics.
• Security Updates: Certain critical software updates or changes to security settings may require passcode authentication to ensure it is genuinely you making these changes.
• Health/Medical Reasons: As mentioned, if Attention Awareness is problematic due to a medical condition, the passcode becomes the primary method.
• Device State: If the iPhone has been off for an extended period or is in a low-power state, it might require a passcode entry to reactivate biometric sensors.

This robust fallback system ensures that your iPhone remains protected, emphasizing that while biometrics are convenient, the passcode is the foundational security element.

Using Apple Watch for iPhone Unlocking

For users who also own an Apple Watch, there's a convenient feature that allows your unlocked Apple Watch to authenticate your iPhone. When enabled, if you're wearing your unlocked Apple Watch and bring your iPhone close to it, the iPhone can automatically unlock without needing Face ID, Touch ID, or a passcode. This feature requires both devices to be on the same Wi-Fi network and Bluetooth to be enabled. It's a particularly useful option when wearing a mask or when the phone is on a surface and difficult to look at directly.

Face ID Security: Beyond Just Unlocking

The security offered by Face ID extends far beyond simply unlocking your iPhone. It's a comprehensive authentication system that underpins many of the secure functions you perform on your device daily. Whether you're authorizing an App Store purchase, logging into supported apps, or confirming transactions like Apple Pay, Face ID provides a seamless and secure method of verification.

The sophistication of the TrueDepth camera system, combined with the software that interprets its data, ensures a high degree of accuracy and security. Apple states that the probability of a random person's Face ID unlocking your iPhone is approximately 1 in 1,000,000, compared to 1 in 50,000 for a 4-digit passcode. This disparity highlights the advanced nature of facial recognition technology when implemented with robust hardware and strict security protocols like Attention Awareness.

Furthermore, Face ID's security is designed to be privacy-conscious. The facial data captured by the TrueDepth camera is encrypted and stored securely on your iPhone, within the Secure Enclave. This data never leaves your device and is not sent to Apple or any third party. It's used solely for authentication purposes and is not shared for any other use, ensuring your biometric information remains private and protected.

Securing App Logins and Purchases

One of the most common uses of Face ID, apart from unlocking the phone, is for authorizing transactions and app logins. When you make a purchase on the App Store, iTunes Store, or Apple Books, Face ID offers a quick and secure way to confirm the transaction. Instead of typing in your Apple ID password, a quick glance at your iPhone is all that's needed.

Many third-party apps also integrate with Face ID for secure login. Banking apps, password managers, and other sensitive applications leverage Face ID to protect your accounts. This integration provides users with a convenient way to access their private data without constantly re-entering passwords, while maintaining a high level of security. The 'Require Attention for Face ID' feature ensures that these sensitive actions are only performed when you are actively looking at your device.

Face ID's encryption within the Secure Enclave is fundamental to its security promise.

Understanding the TrueDepth Camera System

The TrueDepth camera system is the heart of Face ID. It's a sophisticated array of components housed in the notch or Dynamic Island at the top of the iPhone's display. These components work in concert to capture detailed information about your face:

• Flood Illuminator: Emits infrared light to illuminate your face in low light conditions, making it visible to the infrared camera.
• Infrared Camera: Captures an infrared image of your face, registering your facial structure regardless of ambient light.
• Dot Projector: Projects over 30,000 invisible infrared dots onto your face, creating a unique depth map.

This 3D depth map, combined with the infrared image, creates a highly accurate representation of your face. This level of detail is what allows Face ID to distinguish you from others, and what enables the Attention Awareness feature to detect if you are looking at the device.

Privacy and Data Protection

Apple places a strong emphasis on user privacy, and Face ID is a prime example of this commitment. All the facial data collected by the TrueDepth camera is processed directly on the iPhone. It is converted into a mathematical representation and stored in the Secure Enclave, a dedicated security chip within the iPhone's processor. This data is encrypted and is never backed up to iCloud or sent to Apple servers. If Face ID is disabled, or if you choose to reset it, all this data is erased.

The system is designed such that your actual image is never stored, and the mathematical representation cannot be reverse-engineered to recreate your face. This approach ensures that your biometric information remains private and is protected against breaches or misuse. The security of Face ID is therefore built on both advanced technology and strong privacy safeguards.

Face ID and Related Security Concepts

Understanding Face ID involves grasping several related security concepts that ensure its effectiveness and your privacy. The core question, 'do your eyes have to be open to unlock iPhone', directly relates to the 'Attention Awareness' feature, which is a critical component of Face ID's security model. This feature is not merely about recognition; it's about intentional interaction.

Beyond Attention Awareness, Face ID relies on several other principles. The Secure Enclave, a dedicated hardware component within the iPhone's chip, is crucial for protecting your facial data. It's isolated from the main operating system and handles all sensitive biometric information, making it extremely difficult for unauthorized access. This isolation is key to preventing malware or software exploits from reaching your facial data.

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Furthermore, the system is designed to be adaptable. It can learn and adapt to changes in your appearance over time, such as growing a beard or wearing makeup, by updating the stored facial map. This learning capability ensures that Face ID remains functional and convenient without compromising security. When significant changes occur, such as adding an 'Alternate Appearance' or if Face ID struggles to recognize you, it’s an indication that the system is working to maintain its accuracy.

The Role of the Secure Enclave

The Secure Enclave is a vital part of your iPhone's security architecture. It's a separate processor core that handles sensitive data, including your Face ID map. When Face ID scans your face, the data is processed within the Secure Enclave. If the scan matches the stored data, authentication is granted. The data within the Secure Enclave is encrypted and inaccessible to the main processor or the operating system, preventing even Apple from accessing it.

This hardware-level security is a significant advantage. It means that even if the main iOS system were compromised, your facial data would remain protected. The Secure Enclave is also used for other sensitive operations, such as Apple Pay transactions and protecting cryptographic keys, underscoring its importance in the overall security of Apple devices.

Data processed by the Secure Enclave is cryptographically protected and isolated.

Adapting to Your Appearance

One of the remarkable aspects of Face ID is its ability to adapt to changes in your appearance. As you grow a beard, apply makeup, or even wear glasses, Face ID can learn and update your facial data without requiring a full re-setup. This adaptive learning is managed by the system discreetly in the background. When Face ID successfully recognizes you after a slight change, it subtly updates your stored facial data to accommodate the new appearance.

If the changes are more significant, or if Face ID struggles to recognize you consistently, you can manually help it by going to Face ID & Passcode settings and selecting 'Set Up an Alternate Appearance'. This process involves scanning your face again, allowing Face ID to create a more comprehensive facial map that accounts for different looks. This feature ensures that your Face ID remains functional and convenient over time, as your appearance naturally evolves.

Understanding False Rejection vs. False Acceptance

In biometric security, there are two key error rates: False Rejection Rate (FRR) and False Acceptance Rate (FAR). FRR is the rate at which the system fails to recognize a legitimate user (e.g., Face ID fails to unlock your phone even though it's you). FAR is the rate at which the system incorrectly authenticates an unauthorized user (e.g., someone else's face unlocks your phone).

Apple designs Face ID to have a very low FAR (stated as approximately 1 in 1,000,000). This is paramount for security. The FRR can be slightly higher, especially if environmental factors or significant changes in appearance are involved. The Attention Awareness feature plays a direct role in managing FRR by ensuring the system only attempts recognition when the user is actively engaged and looking at the device, thus reducing the chance of accidental rejections due to distraction but also preventing unauthorized access.

When to Consider Disabling Face ID Features

While Face ID is engineered for robust security and convenience, there might be specific circumstances where a user would consider disabling certain features, or Face ID altogether. The primary reason to disable features is usually related to convenience, specific use cases, or addressing persistent issues that cannot be resolved through troubleshooting. The decision hinges on balancing security needs with personal preferences and operational requirements.

The most direct feature related to the initial query is 'Attention Awareness Features'. If a user has a medical condition that prevents them from looking directly at the iPhone, or if they find the requirement too restrictive for their usage patterns, they might consider disabling this. However, this significantly reduces the security by allowing the phone to unlock even if your eyes are closed or looking away, making it vulnerable if the phone is handled by someone else. Therefore, this is a trade-off that should not be made lightly.

Other reasons to consider disabling Face ID entirely could include selling or giving away the iPhone, as all biometric data must be erased. Sometimes, persistent hardware issues with the TrueDepth camera might lead to disabling it, though in such cases, seeking repair from Apple is recommended. Ultimately, the choice is yours, but it's crucial to understand the implications of each setting.

Disabling Attention Awareness Features

As discussed, 'Attention Awareness Features' is the setting that requires your eyes to be open and looking at the iPhone for Face ID to work. If you choose to disable this, your iPhone will unlock via Face ID even if your eyes are closed or looking away. This drastically lowers the security of your device because it allows for unlocking even when you are not actively participating or aware.

Disabling 'Attention Awareness' significantly compromises the security of your Face ID.

Who might consider this? Primarily individuals with specific medical conditions that make direct eye contact impossible or extremely difficult. For the vast majority of users, keeping this feature enabled is strongly recommended to prevent accidental or unauthorized unlocking.

Turning Off Face ID Entirely

You can disable Face ID functionality altogether if you prefer not to use it. This means your iPhone will only be unlockable using your passcode. This is a drastic step, as you lose the convenience and speed of biometric authentication for unlocking, app logins, and purchases. However, it might be considered if:

• You have concerns about the technology itself, despite Apple's security assurances.
• You are experiencing persistent hardware issues with the TrueDepth camera that cannot be resolved.
• You are preparing to sell, trade-in, or give away your iPhone and want to ensure all biometric data is removed.

To disable Face ID entirely, go to Settings > Face ID & Passcode, enter your passcode, and toggle off 'iPhone Unlock'. You can also disable it for other functions like 'iTunes & App Store' or 'Wallet & Apple Pay' independently.

When Face ID Becomes a Necessity to Disable

There are a few critical scenarios where disabling Face ID (or ensuring it's reset) is a necessity:

• Transferring Ownership: When selling, donating, or trading in your iPhone, you must erase all content and settings. This process automatically disables and removes Face ID data. If you are simply handing it over, manually disabling Face ID and then erasing is essential.
• Suspected Compromise: If you have strong reason to believe your device's security has been compromised in a way that might affect your biometric data, disabling Face ID and changing your passcode immediately is a critical step.
• Hardware Malfunction: If Apple Support diagnoses a hardware failure with the TrueDepth camera system and a repair is not immediately possible or desired, disabling Face ID might be a temporary measure while relying solely on your passcode.

In most everyday situations, keeping Face ID enabled with Attention Awareness provides the best balance of security and convenience for your iPhone.