How to turn off app tracking on new apps

When you download and open a new app, you’ll get a notification asking if you want to allow the app to track your activity across other companies’ apps and sites. You will also see information about what the app will track. You can tap Ask Do Not Track to block or allow this activity.
When you download an app, you’ll see a notification pop up that gives you a choice as to whether or not to give the app permission to track you.
An apple
You can also opt out of app tracking across every app you download by going to Settings > Privacy > Tracking and turning off Allow apps to request tracking. This means that any app that tries to ask for your permission will be automatically blocked from asking and telling you that you asked not to be tracked. According to Apple, all apps (other than those you’ve given permission to track in the past) will be blocked from accessing your device’s information used for advertising.
It is important to note that this does not mean that the ads will disappear. It just means that you’ll likely see generic ads, not an ad for the pair of shoes you clicked on once.