What is app tracking transparency?
App tracking transparency (ATT) is an Apple privacy feature that requires apps to ask before tracking your activity across other companies’ apps and websites. Apple introduced ATT in iOS 14 and began enforcing the tracking permission prompt with iOS 14.5 in April 2021, changing how app tracking works on iPhones and other Apple devices.
So, what does app tracking transparency control? In this context, tracking means linking data from one app with data from other companies’ apps, websites, or services — usually for targeted ads, ad measurement, or sharing with data brokers.
ATT also limits access to the identifier for advertisers (IDFA) — a device ID that can help advertisers recognize the same device across different apps. When an app can access the IDFA, it can more easily connect your activity across apps for targeted ads and ad measurement, such as checking whether an ad led you to install, open, or use an app.
Unless you choose to opt in, apps cannot access the IDFA for tracking. ATT applies on Apple platforms where app tracking permission prompts are supported, including iPhone, iPad, and Apple TV.
How does Apple app tracking transparency work?
Once you know what app tracking transparency is, the next part is understanding what happens when an app asks to track you. For you, ATT usually appears as a simple permission prompt:
- 1.When an app wants to track your activity across other companies’ apps or websites, iOS shows a system prompt. This prompt usually asks whether you want to “Allow” tracking or “Ask app not to track.”
- 2.If you tap “Allow,” you opt in to tracking for that app. The app can then access your IDFA and use it for activities like targeted advertising and ad measurement.
- 3.If you tap “Ask app not to track,” the app should not use your IDFA or other identifying data to track you across other companies’ apps and websites.
- 4.Apps are not supposed to bypass this choice. That does not mean every tracking attempt becomes impossible, but apps that ignore your permission choice can violate Apple’s rules and face App Store enforcement.
Apple also offers privacy-preserving ad measurement tools, such as SKAdNetwork and AdAttributionKit, which are designed to measure ad performance without following individual users across apps and websites.
What does ATT actually block?
App tracking transparency mainly limits the data apps can use to follow you outside their own service. For example, it can make it harder for an app to connect what you do in one app with your activity in another app or on a website, then use that combined profile for targeted ads or data sharing.
ATT focuses on third-party tracking. In simple terms, it limits how apps can use your data to recognize you outside their own app without your permission.
Does app tracking transparency stop all data collection?
No, app tracking transparency does not stop all data collection. Apps can still collect first-party data, meaning information about what you do inside that specific app. For example, a shopping app may still see what products you view, what you add to your cart, what you buy, and what account details you provide.
ATT also does not automatically block cross-site tracking, such as cookies, tracking pixels, or analytics tools. For example, a website may still use small tracking technologies to remember your visit, measure activity, or recognize your browser later.
Some companies may try to use device fingerprinting instead. Fingerprinting means piecing together details about your device — such as its model, iOS version, language settings, IP address, or network information — to recognize it without using the IDFA. ATT restricts this workaround in apps, but it does not block every tracking method on the web.
Treat ATT as one privacy layer, not a complete solution. If you want more anonymous browsing, combine ATT with stronger browser privacy settings and extra privacy tools.
How to manage App Tracking Transparency settings on an iPhone
You can manage app tracking transparency directly in your privacy settings on your iPhone or iPad.
One detail can be confusing: Turning off “Allow apps to request to track” does not enable tracking. Instead, it automatically denies future tracking requests, so apps won’t show the ATT pop-up when they request permission to track you. You can also open the “Tracking” menu to see which apps have asked for permissions and change their access.
To change app tracking transparency settings on iPhone:
- 1.Open “Settings.”
- 2.Scroll down and tap “Privacy & security.”
- 3.Tap “Tracking.”
- 4.Turn off “Allow apps to request to track.”
Once the ATT setting is turned off, apps will no longer show tracking prompts, and future requests will be treated as denied. You can still review app permissions for apps previously allowed to track your activity and turn that access off in the same menu.
Should you turn off app tracking?
In most cases, yes. Turning off app tracking requests can reduce the chance of apps, advertisers, and data brokers connecting your activity across different apps and websites.
That said, you may choose to allow tracking for specific apps if you want more personalized ads or app experiences. The choice depends on how much data sharing you are comfortable with, but from a privacy perspective, allowing tracking only for specific apps is better than leaving it open by default.
App tracking transparency on Android: Is there an equivalent?
Android does not have an exact equivalent to Apple’s app tracking transparency feature. On an iPhone, apps must show a tracking permission prompt before they can track you across other companies’ apps and websites. Android does give you some control over ad personalization and advertising IDs, but it does not use the same app-by-app opt-in prompt.
On Android, you can limit some ad tracking by resetting or deleting your advertising ID. This identifier helps advertisers recognize a device for personalized ads, so removing or changing it can reduce some forms of app-based ad tracking.
That said, the exact path may vary depending on your Android version and phone manufacturer. If you cannot find the option, search for “Ads” or “Advertising ID” directly in the settings.
Google’s privacy sandbox for Android is also meant to reduce some forms of ad tracking, but it does not work like Apple’s ATT. You should not expect the same app-by-app tracking pop-up on Android.
Since Android does not use the same ATT prompt, focus on limiting the information apps can use to recognize your device:
- 1.Reset or delete your advertising ID.
- 2.Turn off ad personalization where available.
- 3.Review app permissions regularly.
- 4.Remove permissions that apps do not need.
- 5.Use a VPN for Android to change your IP address and make some forms of online tracking harder.
These steps will not block every tracker, but they can reduce how much data apps, advertisers, and third parties can connect to your device.
What else can you do to protect your privacy?
App tracking transparency is a useful starting point, but it works best alongside other privacy habits. To improve your privacy and mobile security, combine ATT with browser protections, tighter app permissions, and a VPN:
- Use a VPN. A VPN, such as NordVPN, encrypts your traffic and changes your IP address, making it harder to connect your browsing activity to your real location.
- Review app permissions. Check which apps can access your location, camera, microphone, contacts, and photos. Remove permissions that the app does not need.
- Use anti-tracking tools. Tracker blockers can help limit tracking pixels, fingerprinting scripts, and other web technologies used to recognize users across sites.
App tracking transparency can reduce app-based tracking on Apple devices, but it does not make your activity private everywhere. Keep ATT enabled, review app permissions regularly, and use browser and network-level privacy tools to limit tracking beyond apps.
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