What does "Ask App Not to Track" do on iPhone?
Tapping Ask App Not to Track stops that app from reading your iPhone's advertising identifier, and Apple's rules then forbid it from tracking you across other companies' apps and websites in other ways. The app still works fully either way. The prompt arrived in iOS 14.5.
The prompt comes from App Tracking Transparency. Apple defines tracking as linking data about you from one app with data from other companies' apps and websites for targeted ads or ad measurement, or sharing it with data brokers. If you say no, the app gets an advertising identifier made of all zeros. Apple's rules also bar it from using your email address or a device fingerprint instead.
The zeroed ID is enforced by iOS itself. The rest is enforced through Apple's App Store review and developer agreement, so an app that breaks the rules may not be caught right away. Saying no also doesn't stop an app from collecting data about what you do inside it. It limits linking your data with other companies, not all collection.
- Tap Ask App Not to Track when the prompt appears, unless you want ads based on your activity elsewhere
- Review apps you've allowed in Settings, Privacy & Security, Tracking
- Turn off Allow Apps to Request to Track there to treat every app as if you said no
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Tracking & Privacy Labels
From the iPhone Privacy Controls course. See what Ask App Not to Track really blocks and how to read an app's label.
Try it on the simulated phone Read the full lesson
The reading is free. The hands-on lab is part of Pro.