Theft Detection Lock uses AI, a phone’s motion sensors, Wi-Fi and Bluetooth to detect if someone takes the device and runs, bikes or drives away, and then locks the screen, according to Google’s Android Help article. The setting is in the Theft protection menu of the Google settings on Android.

Google says the lock is there to protect the content on the phone after a grab.

Some of the steps work only on Android 10 and up, and the theft protection features are not supported on Android Go devices, tablets or wearables. Support can also vary by phone model. A screen lock must be set on the device before any of these features can be turned on.

How to turn it on

Google’s article describes the path on an Android phone as follows.

  1. Open your device’s Settings app.
  2. Tap Google > All services > Theft protection.
  3. Turn on Theft Detection Lock.

If the “Theft Detection Lock” setting is greyed out, Google says the device does not support the feature. Menus can differ on some phones, so the path above is the one Google’s article describes, and it may not match every model.

Some theft protection features may already be on by default, and Google points to the manufacturer’s guide for details on a given device.

When it may not trigger

The lock is not active while the phone’s screen is already locked.

To limit interruptions during normal use, Google says Theft Detection Lock may not trigger when the device has a stable Wi-Fi connection, a stable Bluetooth connection, or both. It may also stay quiet if there were repeated locks in a short period of time.

If the phone locks while in use, the advice is to unlock it and carry on. The article adds that Google will “continue to improve the feature to minimize interruption to normal use.”

Offline Device Lock

The same Theft protection menu holds a second setting called Offline Device Lock.

Offline Device Lock locks the screen after the device goes offline. Google gives the example of a thief turning off the internet so the phone cannot be found with Find Hub. After a short period of being used offline, the device locks. The phone must be unlocked at the moment it loses its connection.

To turn it on, open Settings, tap Google > All services > Theft protection, then turn on Offline Device Lock.

Remote Lock, also in that menu, lets a lost or stolen phone be locked from android.com/lock with a verified phone number, and if the device is offline when the request is sent, the screen locks once it is back online. Google says Offline Device Lock can lock the screen twice in a 24-hour period.

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