Android Theft Detection Lock Knows When Your Phone Is Stolen

Google is introducing new AI-powered safety tools in Android that can lock down your phone if thieves nab it.
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Courtesy of Google

Billions of Android phones are getting new tools to stop phone thieves from accessing your information and to slow down their criminal behavior, Google announced today at its I/O developer conference. Android phones will soon use artificial intelligence to automatically detect when they have been snatched from your hand and lock themselves, as part of the new changes that include adding extra protections to secure your phone if it has been stolen.

The upgrades—some of which will come with the Android 15 operating system, while others will be compatible with older phones—come as phone companies are increasingly building extra measures into their software to thwart rampant levels of phone thefts and further protect people’s data. As well as the stolen phone tools, Google is introducing new changes to Android 15 that will scan how apps are using “sensitive permissions” in real time to detect potentially suspicious app activities.

Around the world, phone thefts are a huge problem—in London, for example, a phone is stolen every six minutes. Thieves riding electric bikes or scooters can snatch phones out of people’s hands, pickpockets can easily nab devices from bags, and others are known to peer over shoulders to learn a phone’s PIN before they steal the device.

Stolen phones can be resold if they are unlocked or passed on to others who can break them down for parts and sell those components. However, some criminals will also try to access banking or crypto apps and transfer money. “The thieves profit from the physical device themselves, but they also increasingly are trying to get into the content of the device, where the most valuable data is stored,” Jianing Sandra Guo, an Android security and privacy product manager at Google, tells WIRED. Some thieves, if they have a locked phone, spam people with phishing emails and messages to friends to try and get login details.

Google’s anti-theft tools have been designed to add more protection before a phone is stolen, during the theft, and after a phone has been taken, Guo explains. In keeping with Google’s and the wider tech industry’s push, some of these have been built using artificial intelligence as a key component.

Android Update Theft Detection Lock Knows When Your Phone Is Stolen
Courtesy of Google

Android’s new Theft Detection Lock uses Google’s AI to determine when your phone has been snatched from your hand. If it detects this, the phone’s screen will automatically be locked. Using smartphone sensors, such as the accelerometer and gyroscope, Google trained its algorithms to detect sudden changes in the phone’s positioning and the motions that might indicate it has been snatched.

“There’s a grabbing of the phone, changing hands, and then an attacker running, biking, or even driving away with a device,” Guo says. To train the algorithm, Google’s research staff studied how phones are commonly stolen, then its teams re-created snatching events against each other to collect data about what a simulated theft looks like.

Thieves stealing phones, Guo says, will often open the camera app when they don’t know the phone’s PIN, to stop them from losing access to the device. They also often try to disconnect it from cell networks for a long period of time so they can’t be locked out of the device remotely. The company’s new Offline Device Lock will lock your screen when the phone is offline for an extended period of time, if the setting is turned on.

To increase protections before a phone is stolen, Google says in a blog post, the company is adding four data protection features that can help keep your information locked down. The first stops your phone from being set up after a factory reset, unless the person knows your login details. “This renders a stolen device unsellable, reducing incentives for phone theft,” Google vice president Suzanne Frey writes.

There’s also a new “private spaces” option where you can store sensitive apps, such as banking apps, that require a second PIN or use of your biometrics, such as a fingerprint, to access. There are also extra authentication controls being put in place: If a thief tries to disable Google's Find My Device location-tracking service they will need to also use your PIN, password, or biometric information to unlock it. If a thief does know your PIN, it will also be possible to turn on the need for biometric authentication to make changes to important Google account and device settings, such as a PIN change or turning off anti-theft settings.

The extra authentication features are similar to those introduced by Apple in its Stolen Device Protection system that debuted in iOS 17.3 earlier this year, although Google’s theft motion detection goes further than these tools. The aim of all anti-theft options is to lock down the information stored on phones but also to make it harder for criminals to abuse devices when they have them. Making it more difficult for criminals to resell phones or transfer money may help to deter thefts.

If your phone does get stolen, Android already allows phones to be locked and wiped. However, Guo says, the experience of having a phone swiped from your hands is a “traumatic” experience, and in the aftermath, people may not remember all their Google account login details to close off access to the phone. To address this, Google’s new Remote Lock feature will allow people to lock their phone using just a phone number. “The content of the device is protected, and it buys the user a lot of time … to be able to organize themselves and do further remediation,” Guo says.

Google’s new protections around factory resets will launch with Android 15, while some of the other features will be available later this year. Guo says that, where possible, Google has tried to make the features work on versions of the software as old as Android 10.

Aside from the anti-phone-theft tools, Android is coming with other security and privacy updates. Google’s app safety system, Google Play Protect, scans billions of apps every day to detect malware, but now this is being expanded to do live scanning on people’s phones to better detect suspicious behavior. “With live threat detection, Google Play Protect’s on-device AI will analyze additional behavioral signals related to the use of sensitive permissions and interactions with other apps and services,” Dave Kleidermacher, a Google vice president, writes in a blog post.

Other security-related updates to Android 15 include hiding notifications and one-time passwords from appearing if you are sharing your phone’s screen with others, hiding login details if you are logging in to an app or website while sharing your screen, and identifying when cell connections are unencrypted and alerting people if there is a “potential false cellular base station” or IMSI catcher nearby that is logging a user’s phone.

Updated 2:45 pm ET, May 15, 2024, to clarify that several new features will be included in updates that are separate from Android 15 itself, according to Google.