We have all had that moment when you pick up your phone and all is not as it seems – and you wonder if someone else has been looking at it.
Thankfully, it's relatively easy to tell if someone has been be looking through your device as snoopers leave a digital 'paper trail' that is simple to follow.
How can I tell if someone's been on my phone?
A good first stop is your screen time controls, where you get a detailed history of what apps have been opened that day. On iPhone, go to Settings > Screen Time, then See All App and Website Activity, then Day to see a daily summary of app use - this can't be manually altered, so if there are apps you haven't used recently in there, it's pretty certain someone else has.
On Android, this may vary slightly by manufacturer, but if you go to Settings > Digital Wellbeing and Parental Controls, you can see a daily report of which apps you have been using. From this menu, you can also opt to see how many notifications have been received on your phone – so if there are some you don't remember getting, this could also be a warning sign that a snooper has been reading yours.
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The other common way a snooper might betray themselves is through your app carousel on iPhone or app history on Google, which show you your most recent apps. To access this on iPhone or Android, swipe up from the bottom of the screen, hold and then let go. This shows recently accessed apps in chronological order, so if there's an app you don't remember opening, it's a clear warning sign.
How can I stop someone snooping on my phone?
The obvious way to stop someone looking through your phone is to ensure that no-one knows your PIN code – but this sometimes isn't possible (for instance, if you live with a partner who you are worried might snoop through your device).
But there are other security measures you can use. If you're worried someone is going to go through your phone, Android's Screen Pinning and iPhone's Guided Access can help. Both of these lock an unwelcome guest away from your private data.
On Guided Access, the user is locked inside a single app, and it has a separate passcode, so that even if someone knows your PIN they can't get out. Go to Settings > Accessibility, then turn on Guided Access, and then add your passcode. To start Guided Access – for when you're leaving your phone somewhere you’re worried someone might spy on it – open an app, triple-click the side button, tap Guided Access, then select Start.
Android's Screen Pinning is similar, locking the user inside one app, and it's only possible to get out if they know your PIN.
Dedicated 'locking' apps including Samsung Secure Folder and AppLock. Norton App Lock can also help, creating PIN codes to lock certain apps. It's also worth checking the apps you use to see if they offer additional security features – WhatsApp, for instance, lets you lock the app with a fingerprint, so that people snooping on your phone can't read your messages.
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