App Tracking Transparency (ATT) is a feature introduced by Apple in iOS 14.5 that requires apps to obtain user permission before tracking their activity across other apps and websites. This means that when you open an app, you may see a prompt asking if you want to allow the app to track your data for advertising purposes. The goal of ATT is to enhance user privacy by giving individuals more control over their personal information. Users can choose to either allow or deny tracking, which can impact how advertisers target them and how apps collect data for personalized experiences.