Can a Smartwatch Unlock Your Phone or Computer?

How smartwatch unlock features work

A smartwatch unlocks your phone or computer by acting as a trusted device that is already authenticated. When you want to unlock your phone, the phone checks that the watch has an active, unlocked session and that the two are physically close to each other. The phone then skips the normal PIN, password, or fingerprint prompt.

The communication link is Bluetooth. The Bluetooth radio in the watch and the phone exchange data over the 2.4 GHz ISM band, and the phone uses signal strength to estimate distance. The latest Bluetooth standard adds a feature called Channel Sounding that improves distance accuracy, so a phone can tell whether a watch is truly on your wrist rather than on a table a few meters away.

• The unlock triggers only when the watch is already unlocked (for example, after you enter its passcode or it detects your wrist).
• If the watch is not on your wrist or has been idle too long, the phone falls back to the regular unlock method.
• Bluetooth LE is designed for very low power operation, so the constant proximity check has a minimal effect on battery life.

Apple Watch: iPhone and Mac unlock

Apple Watch can unlock a paired iPhone, but only when the iPhone has Face ID and only in specific situations. When you wear an Apple Watch with a passcode and raise your wrist while wearing a mask, the iPhone recognizes the watch as a trusted device and unlocks without Face ID. This works because the watch and iPhone are paired, the phone is on the same Wi-Fi or Bluetooth network, and the watch is already unlocked. The iPhone must be using iOS 14.5 or later, and the Apple Watch must have a passcode enabled.

Apple Watch can also unlock a Mac, but the Mac must be a model from 2013 or later with an Apple T2 chip or an Apple silicon chip. When you walk up to your Mac with your Apple Watch on your wrist, the Mac uses the watch as a proximity authentication device. The Mac must have Bluetooth on, the same Apple Account (formerly Apple ID) must be signed in, and the watch must have a passcode. The unlock will not happen if the watch is in Power Reserve mode or if wrist detection is off.

For iPhone unlock, the Apple Watch must be on the same Wi-Fi or Bluetooth network as the phone. For Mac unlock, the two devices need to be within Bluetooth range of each other. If you lose your iPhone or Mac, you can use your Apple Watch with the Find My app to locate them.

Wear OS and Android: Smart Lock and more

Wear OS by Google is the operating system used on Google Pixel Watch, Samsung Galaxy Watch, and many other Android smartwatches. Wear OS watches can unlock an Android phone using a Google feature called Smart Lock, which lets your phone stay unlocked when it is near a trusted Bluetooth device. This is separate from the watch being an unlocked companion; it is the phone trusting the watch's Bluetooth signal.

Smart Lock has a few trust options: on-body detection, trusted places, trusted devices, and trusted face. When you pair a Wear OS watch with an Android phone, you can add the watch as a trusted device. The phone stays unlocked as long as the Bluetooth connection is active. If you walk away or the phone loses the Bluetooth signal, the phone locks again.

This feature exists on Android phones running Android 5.0 (Lollipop) or later, and it works with any Wear OS watch that has an active Bluetooth connection. Some Android phones from manufacturers like Samsung or Google also have their own proximity unlock modes that use the watch's sensors, but Smart Lock is the universal option.

On the other hand, Wear OS watches can also unlock the phone when you wear them. If you raise your wrist and the watch has been unlocked, the phone can use the watch as a second authentication factor. This is similar to how Apple Watch is used, but it requires that both devices are on the same Google Account and have the Google Smart Lock setting enabled.

Platform limits: what works and what does not

The unlock feature is not universal. An Apple Watch will only unlock an iPhone or a Mac, not an Android phone or a Windows PC. A Wear OS watch (Google Pixel Watch, Samsung Galaxy Watch, and others) will only unlock an Android phone, not an iPhone or a Mac. Garmin, Fitbit (now part of Google), and Amazfit watches do not offer any unlock functionality for phones or computers; they are fitness-first devices that handle notifications, not device authentication.

The reason is that unlock requires deep operating system integration. The phone or computer has to trust the watch as a hardware key, which means the watch must run the same ecosystem's authentication stack. Apple does this with Apple Watch and macOS or iOS, while Google does it with Wear OS and Android. No third-party watch can replicate this because the authentication relies on proprietary OS-level APIs.

If you want this convenience, choose a watch from the same ecosystem as your phone or computer. That means an Apple Watch for iPhone or Mac users, and a Wear OS watch for Android phone owners. See our guides for the best Apple watches and best Wear OS watches to compare models.

Convenience versus security: what you should know

Using an unlock feature reduces friction: you do not need to type a passcode every time you pick up your phone. But it also changes your security posture. If your phone is set to require a passcode after a short timeout, and you have a watch with unlock enabled, anyone who has your watch and your phone can unlock both. For that reason, all unlock features require that the watch itself is locked with a passcode and that wrist detection is on, so the watch locks when you take it off.

There are also implications for data privacy. The phone and watch exchange signals that can reveal your location and your proximity to the other device. Bluetooth and Wi-Fi proximity checks have been used to track people in the past, so manufacturers have added randomization: the phone's MAC address changes periodically, and proximity checks use secure ranging. The Bluetooth LE radio uses frequency hopping and secure cryptographic techniques to prevent an attacker from impersonating your watch.

If you are concerned about privacy, use a passcode as the primary unlock method and only enable proximity unlock for low-risk situations, such as unlocking your phone while you are at home. When you are in a public place, you can disable the unlock feature from the watch or the phone settings. The phone will then fall back to the standard unlock method.

For children, the same security rules apply. A child's watch that can unlock a phone should have the same passcode and wrist detection requirements. The FTC's COPPA Rule governs what personal information can be collected from children under 13, including their physical location and biometric identifiers. Some children's smartwatches collect location and audio data, so review the privacy policy before setting up an unlock feature for a child.

What to pick for your use

If the unlock feature is important to you, your choice comes down to two ecosystems. Apple Watch owners get iPhone and Mac unlock as a built-in feature. Wear OS owners get Android Smart Lock, which is less polished but still works. There is no third-party watch that can unlock a phone without being from the same ecosystem, because the feature requires OS-level integration.

The rest of the smartwatch features you want will narrow the field. If you want a cellular connection so you can leave your phone behind, see our best cellular smartwatches guide. If you want a rugged Garmin for outdoor adventures, accept that it will not unlock your phone, but it will give you GPS and battery life. Read the smartwatch platform article to understand how the OS affects your options.

Before you buy, check that your phone model is compatible with the watch you want. The smartwatch phone compatibility guide explains which phones work with which watches. And if you already own a watch and want to know whether it can unlock your computer, consult the maker's support page; the answer is usually no for non-Apple, non-Wear OS watches.

What to pick for your use

Questions

Can a smartwatch unlock an iPhone?

Yes, but only an Apple Watch. Apple Watch can unlock an iPhone with Face ID when the watch has a passcode and wrist detection enabled, and the iPhone is on the same network. No other smartwatch can unlock an iPhone because the feature uses Apple's proprietary authentication.

Can a Wear OS watch unlock an Android phone?

Yes. Use the Google Smart Lock feature on your Android phone. Add your Wear OS watch as a trusted device, and the phone will stay unlocked when the Bluetooth connection is active. This works with Google Pixel Watch, Samsung Galaxy Watch, and other Wear OS watches.

Can a Garmin or Fitbit watch unlock my phone?

No. Garmin and Fitbit watches do not include an unlock feature. They can show notifications and control music, but they cannot act as a trusted device for your phone's lock screen.

Is it safe to use a smartwatch to unlock my phone?

It is reasonably safe if you set a passcode on the watch and keep wrist detection on. The watch locks when removed, so the phone will not unlock if an unauthorized person finds the watch. The phone also checks Bluetooth proximity to ensure you are close.

Why doesn't my watch unlock my phone even though it is paired?

Check that you have enabled the unlock feature in the phone and watch settings. For Apple Watch, ensure the iPhone has Face ID and the watch has a passcode and wrist detection. For Wear OS, verify Smart Lock is active and the watch is set as a trusted device. Bluetooth must be enabled on both.