The short answer: on an iPhone, open Settings > Privacy & Security and work through five settings: Tracking, Location Services, Apple Advertising, what’s allowed on your Lock Screen, and Safety Check. Each takes a minute or two, and none of them stops your phone from working normally. Android steps are at the end. Ads that seem to “know” what you said usually come from this kind of tracking, not from the microphone (FTC). To check the microphone too, see which apps are using your microphone.
1. Stop apps from tracking you across other apps
- Go to Settings > Privacy & Security > Tracking.
- Turn off Allow Apps to Request to Track. Apps then can’t use your phone’s advertising identifier to follow you across other companies’ apps and websites (Apple).
2. Limit which apps know where you are
- Go to Settings > Privacy & Security > Location Services. Keep Location Services on. Turning it off stops many important features, like Maps and Find My (Apple).
- Tap each app and choose Never, Ask Next Time or While Using the App. Games and shopping apps rarely need your location.
- For apps that only need your general area, such as weather, turn off Precise Location (Apple).
- Optional: tap System Services, then Significant Locations & Routes. This is a history of places you visit often. Apple says it’s encrypted and can’t be read by Apple. Tap Clear History to delete it, or turn it off (Apple).
3. Turn off personalized Apple ads
Go to Settings > Privacy & Security > Apple Advertising and turn off Personalized Ads. This affects ads Apple shows in the App Store, Apple News and Stocks. You may see just as many ads, but they’ll be less targeted (Apple).
4. Limit what works while your iPhone is locked
- Go to Settings > Face ID & Passcode (or Touch ID & Passcode on an iPhone with a Home button) and enter your passcode.
- Under Allow Access When Locked, turn off anything you don’t need on the Lock Screen, such as replying to messages or Wallet (Apple).
Apple notes the trade-off: turning these off stops someone holding your phone from seeing your information, but you lose the shortcut too (Apple). Keep your Medical ID available for emergencies; see how to set up Medical ID.
5. Run Safety Check
Go to Settings > Privacy & Security > Safety Check and tap Manage Sharing & Access. It walks you through who can see your location, which apps can use your data, and which devices are signed in to your Apple Account. It needs iOS 16 or later (Apple). It’s worth doing once a year, or any time you’re worried someone has access to your phone.
The same settings on Android
- Location: open Settings > Location > App location permissions, tap an app and choose Allow only while using the app, Ask every time or Don’t allow (Google).
- Location history: Google’s Timeline saves the places you visit. It’s off by default. You can check it, or turn it off, in your Google Account’s activity settings (Google).
- Advertising ID: you can reset or delete your phone’s advertising ID (Google). Search Settings for Ads to find it.
- Microphone and camera: see our microphone permissions guide.
Samsung and other phone makers sometimes use different menu names. Use the search bar at the top of Settings if you can’t find one.
What not to turn off
- Software updates. They fix security holes. See how to install updates safely.
- Location for emergency calls and Find My. These help you, not advertisers.
- Your passcode, Face ID or fingerprint lock.
