Apps can ask to track what you do across other companies' apps and websites. They use it for advertising or pass it on to data brokers.
If you leave it
While the switch is on, every app may ask you. One quick tap on Allow is enough for that app to track you.
Where to find it
Settings
Privacy & Security
Tracking
Turn off: “Allow Apps to Request to Track”
Step by step
1.
Open Settings and tap Privacy & Security.
2.
Tap Tracking.
3.
Turn off Allow Apps to Request to Track. Every app that asks from now on is treated as if you had tapped Ask App Not to Track. You can also ask all apps you allowed earlier to stop tracking you.
4.
On the same screen you see a list of apps that asked to track you. Turn tracking off for each one you don't want.
Path from the official guide by Apple for iOS 14.5, as of 3 Oct 2026.