How iPhone App Tracking Works

App Tracking Transparency (ATT), introduced in iOS 14.5, requires apps to ask your permission before tracking your activity across other apps and websites. Tracking is used primarily to serve targeted advertising and to measure ad campaign effectiveness. When you decline tracking, apps cannot link your activity to advertising networks or share your data with third parties for ad targeting.

Disable Tracking Globally

  1. 1

    Settings → Privacy & Security → Tracking

    Open Settings. Tap Privacy & Security. Tap Tracking.

  2. 2

    Toggle off “Allow Apps to Request to Track”

    Turning this off prevents all apps from asking for tracking permission. All existing apps that previously had tracking permission have it revoked. You will no longer see tracking permission pop-ups from any app.

Review Individual App Tracking Permissions

On the same Tracking screen, below the toggle, all apps that have requested tracking are listed with their current permission. Tap any app to change its setting. This allows you to allow tracking for specific apps (e.g. a rewards app where personalisation is genuinely useful) while blocking others.

Other Privacy Settings Worth Checking

  • Location Services: Settings → Privacy & Security → Location Services. Review which apps have Always, While Using, or No location access.
  • Ad targeting: Settings → Privacy & Security → Apple Advertising → turn off Personalised Ads to reduce Apple’s own ad targeting within their apps.
  • Analytics sharing: Settings → Privacy & Security → Analytics & Improvements → turn off Share iPhone Analytics to stop usage data going to Apple.
Does blocking tracking affect how apps work?Most apps function identically without tracking permission — tracking is for advertisers, not core app functionality. Social media apps may show less personalised ads (or the same ads, just less targeted). Some loyalty and rewards apps may offer reduced personalisation. Games may not be able to show ads from networks that require tracking, which can affect ad-supported free games.

Frequently Asked Questions

ATT blocks the IDFA (Identifier for Advertisers) — the main tracking identifier apps use across other apps. Apps can still collect data within their own app and may use other tracking methods (fingerprinting, login data). ATT significantly reduces cross-app tracking but is not a complete privacy solution. For stronger privacy: also use Safari instead of Chrome (Safari has Intelligent Tracking Prevention), enable Private Relay (iCloud+ subscribers), and use a VPN on public WiFi.
App tracking (covered by ATT) refers to tracking your activity across different apps and websites for advertising purposes — linking what you do in App A to what you see advertised in App B. Location tracking is a separate permission that allows apps to know where you are physically. Both are controlled separately in iOS privacy settings. You can allow location access for maps and delivery apps without allowing cross-app tracking for advertising.