Galaxy Tab S4 Iris Scanner: Does It Have One?

The Samsung Galaxy Tab S4 does not have an iris scanner. Instead, it relies on facial recognition and a fingerprint sensor for biometric security. This article explains what the Tab S4 actually offers, how its face unlock compares to iris scanning, and what you should know before buying or using one.

What the Galaxy Tab S4 Actually Has

The Galaxy Tab S4, released in August 2018, was Samsung’s flagship Android tablet at the time. Its biometric options are:

Facial recognition – a 2D camera-based system that unlocks the tablet by analyzing your face.
Fingerprint sensor – located on the rear of the device, below the camera.
Pattern, PIN, or password – standard fallback methods.

There is no dedicated iris scanner hardware (no infrared camera) on the Tab S4. This is a common point of confusion because several Samsung phones from the same era, like the Galaxy S9 and Note 8, did include iris scanning. The Tab S4 was positioned as a productivity device, and Samsung chose to omit the iris sensor to keep costs down and the tablet thinner.

Why People Think It Has an Iris Scanner

Two factors drive the confusion:

Similar naming: The Galaxy Tab S4 was announced alongside the Galaxy Note 9, which had an iris scanner. Many users assumed the tablet shared the same feature set.
Face unlock similarity: Samsung’s face recognition on the Tab S4 can feel like iris scanning because it unlocks quickly and works in low light (it uses the screen brightness to illuminate your face). But it is not the same technology – it does not map your iris pattern.

If you read an old spec sheet that says “face recognition” and interpret it as “iris scanner,” you might walk away with the wrong idea.

How Face Recognition on the Tab S4 Works

The Tab S4 uses the front-facing 8MP camera to capture a 2D image of your face. It then compares that image to the one you recorded during setup. This is the same basic approach used by many Android devices from 2016–2019.

Because it is 2D, it can be fooled by a photo of you. It also struggles in very dark environments (unless you enable the “raise to wake” and the screen brightens). It does not use infrared, so it cannot work in complete darkness.

To set it up:

Go to Settings → Biometrics and security → Face recognition.
Register your face in a well-lit room.
Choose whether to require your eyes to be open (recommended for security).
Select a fallback method (PIN, pattern, or password).

Once set up, you can unlock the tablet by pressing the power button and looking at the screen. The face unlock is fast but less secure than an iris scanner or fingerprint.

Iris Scanner vs. Face Recognition: Key Differences

If you are comparing the Tab S4 to devices that do have iris scanning (like the Galaxy S9 or Note 8), here is what changes:

Security: Iris scanning uses infrared to map the unique patterns in your iris – far harder to spoof than a 2D photo. Face recognition on the Tab S4 can be bypassed with a printed picture.
Low light: Iris scanning works in pitch darkness because it uses infrared. Face recognition needs some light.
Speed: Iris scanning is slower because it requires you to hold the device at eye level. Face recognition is often faster but less reliable at angles.
Glasses and contacts: Iris scanning can fail with heavy glasses or certain contact lenses. Face recognition generally works fine with glasses.

For everyday convenience, face recognition is fine. For sensitive data, the fingerprint sensor on the Tab S4 is the better choice.

Common Problems and Workarounds

Tab S4 owners sometimes report issues with face unlock. Here are typical fixes:

“Face not recognized” in low light: Turn on “Increase brightness” in face recognition settings, or use a PIN.
Face unlock not available: Make sure you have a secure lock method (PIN/pattern) set first. Face recognition cannot be used as the only lock.
Slow to unlock: Disable “Stay on lock screen” so it doesn’t wait for you to swipe.
Fails with sunglasses or hats: Re-register your face with those accessories on, or remove them.

If you absolutely need iris-level security, the Tab S4 is not the right device. You would need a newer Samsung tablet (like the Tab S7 or S8 series, which have improved face recognition but still no iris scanner) or a phone with an iris sensor.

What to Do If You Want Iris Scanning

If iris scanning is a must-have, you have limited options:

Samsung phones: Galaxy S9, S9+, Note 8, Note 9, and the Galaxy S8 series all have iris scanners. They are older but can serve as secondary devices.
Windows Hello devices: Many Windows laptops and tablets (like the Surface Pro series) use infrared cameras for facial recognition that is comparable to iris scanning in security.
Third-party apps: No app can add iris scanning to the Tab S4 because it lacks the required infrared hardware. Any app claiming to do so is not genuine.

If you already own a Tab S4, the best security is the fingerprint sensor. It is fast, reliable, and cannot be fooled by a photo.

Frequently Asked Questions

Does the Galaxy Tab S4 have an iris scanner?

No. The Tab S4 does not have the infrared hardware needed for iris scanning. It uses 2D facial recognition and a rear fingerprint sensor.

Can I add an iris scanner to my Tab S4?

No. Iris scanning requires a dedicated infrared camera and emitter. The Tab S4 lacks these components, and they cannot be added via software or an external accessory.

Is face recognition on the Tab S4 secure?

It is convenient but not highly secure. A high-resolution photo of your face can unlock the tablet. For better security, use the fingerprint sensor or a strong PIN.

Why did Samsung skip the iris scanner on the Tab S4?

Samsung likely chose to differentiate the tablet from its flagship phones and reduce manufacturing costs. The Tab S4 was aimed at productivity, where a fingerprint sensor was considered sufficient.

Which Samsung tablets have an iris scanner?

None of Samsung’s tablets have ever included an iris scanner. Only certain Samsung phones (Galaxy S8, S9, Note 8, Note 9) have that feature.

Does the Tab S4 face unlock work in the dark?

Only with the “Increase brightness” option enabled, which uses the screen as a flashlight. It is not true night vision like an iris scanner.

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