Apps must show Apple's App Tracking Transparency (ATT) prompt and receive permission before tracking users across other companies' apps and websites or accessing the advertising identifier (IDFA). You can show an explanation screen before the system prompt to describe the benefit, but you cannot incentivize consent, mimic the system dialog, or restrict features for users who decline. Timing the prompt after users see value and writing a clear purpose string improve opt-in rates.
What ATT requires
Since iOS 14.5, apps must request permission through the AppTrackingTransparency framework before tracking. Apple defines tracking as linking user or device data collected from your app with data from other companies' apps, websites, or offline properties for targeted advertising or advertising measurement, or sharing such data with data brokers. Accessing the IDFA requires permission.
If your app does not track, you do not need to show the prompt, and your App Privacy details should say so. If it does, you must include a purpose string explaining why, and respect the user's choice. Users can also turn off tracking requests globally, in which case apps cannot show the prompt.
Apple's rules for prompts and pre-prompts
You may show a screen before the system prompt to explain why you ask, such as supporting free content through relevant ads. Apple's guidelines prohibit offering incentives for allowing tracking, such as rewards or features, and prohibit restricting functionality for users who decline. Pre-prompt screens must not look like the system dialog or use confusing language.
The system prompt itself shows your app name and your purpose string, with options to allow or ask the app not to track. You can show it only once per install; afterward, users must change the setting in iOS Settings. That makes timing and context critical. See our explainer on the App Store Review Guidelines for related privacy rules.
When to show the prompt
Showing ATT on first launch, before users understand the app, tends to produce lower opt-in rates. Many apps wait until after onboarding or a first success moment, when users trust the app more. However, delaying too long can miss users who churn early, and some ad networks benefit from consent early in the lifecycle.
Test timing. Compare opt-in rates and downstream metrics for prompts after onboarding, after a key action, or at a natural pause. Our onboarding best practices guide covers sequencing permission requests so they do not overwhelm new users.
Write a clear purpose string and pre-prompt
The purpose string should explain the benefit in plain language, such as This helps us show you ads that are more relevant and keep the app free. Avoid vague or misleading text. Apple reviews purpose strings, and unclear ones can lead to rejection.
A pre-prompt can expand on the explanation with friendly visuals and honest framing. Keep it short, make the choice clear, and avoid pressure. Some apps let users dismiss the pre-prompt without showing the system prompt, preserving the one-time opportunity for a better moment.
What opt-in rates look like
Opt-in rates vary widely by category, audience, region, and prompt design. Industry reports from attribution providers have commonly shown average opt-in rates among users who see the prompt in roughly the 20 to 40 percent range, with games often higher than some other categories. Your own rate depends heavily on trust, timing, and messaging.
Treat external figures as context, not targets. Track your opt-in rate by app version, prompt timing, and country, and test improvements. Even a modest increase can improve ad measurement and targeting for networks that use consented data.
Measuring without consent
For users who decline, measurement relies on privacy-preserving methods such as SKAdNetwork and AdAttributionKit for ad attribution, aggregated store analytics, and modeled reporting from ad platforms. Apple Ads uses the AdServices framework, which can attribute installs from its campaigns within Apple's privacy rules.
Build your measurement strategy assuming many users will decline. Our SKAdNetwork and AdAttributionKit guide explains how to design conversion values, and attribution and organic uplift covers incrementality testing.
Android: advertising ID and privacy
Android does not have an identical system prompt, but users can delete or reset their advertising ID, and apps targeting Android 13 and later must declare the AD_ID permission to access it. Google Play's policies govern how advertising IDs and user data may be used, and the Data safety form must reflect your practices.
Treat privacy consistently across platforms. Users increasingly expect transparency, and regulators in many regions enforce consent rules such as the GDPR. Our guide to privacy labels and Data safety explains disclosure.
Common ATT mistakes
Showing the prompt immediately on first launch with no context is the most common mistake. Another is designing pre-prompts that resemble the system dialog or pressure users, which breaches Apple's guidelines. Some apps offer rewards for consent, which is prohibited.
Teams also show the prompt when they do not actually track, adding friction for no reason, or fail to update App Privacy details to match tracking behavior. Finally, building measurement that depends on high consent leaves campaigns blind for the majority who decline.
A worked example: a free puzzle game
A free puzzle game shows the ATT prompt on first launch and sees low opt-in. It moves the prompt to after the player completes the third level, preceded by a friendly screen explaining that ads keep the game free and allowing tracking makes ads more relevant.
The purpose string is rewritten in plain language. Opt-in rises meaningfully, and ad revenue per user improves for consenting players. The team also redesigns its SKAdNetwork schema to capture level completion and first purchase, improving measurement for players who decline.
How to do it, step by step
- Confirm whether you trackReview SDKs and data flows to determine if your app tracks under Apple's definition.
- Write a clear purpose stringExplain the benefit honestly in plain language.
- Design a compliant pre-promptExplain why you ask without incentives, pressure, or system-like design.
- Test prompt timingCompare first launch, post-onboarding, and post-success moment prompts on opt-in and retention.
- Build consent-independent measurementSet up SKAdNetwork or AdAttributionKit and aggregated reporting for users who decline.
Before and after examples
Illustrative examples written for a generic app in this category, not client results. Swap in your own product, audience, and data.
We need this permission.
This helps us show you ads that are more relevant and keep the game free.
Why it works: A clear benefit improves trust and meets Apple's expectations.
Prompt on first launch.
Prompt after the third level, preceded by a short explanation.
Why it works: Users who enjoy the app first are more likely to allow tracking.
A screen styled like the system alert with a big Allow button.
A friendly branded screen explaining ads, with a clear Continue button.
Why it works: Mimicking the system dialog breaches guidelines.
Action plan
- Show ATT only if you track
- Write an honest purpose string
- Use a compliant pre-prompt
- Test prompt timing
- Never incentivize consent
- Measure with SKAdNetwork for users who decline
Metrics to monitor
- ATT opt-in rate
- Opt-in rate by prompt timing and country
- Ad revenue per user by consent status
- Share of installs attributed via SKAdNetwork
- App Review rejections related to privacy
Record the baseline, release date, audience, markets, and external changes before interpreting movement. Rankings and conversion are useful signals, but a decision is stronger when activation, retention, and business value confirm that the page attracted the right users.
Frequently asked questions
Do all iOS apps need the ATT prompt?
No. Only apps that track users across other companies' apps and websites, or access the IDFA, need it.
Can I explain ATT before showing the prompt?
Yes. A pre-prompt explanation is allowed if it is honest, does not mimic the system dialog, and does not offer incentives.
What is a typical ATT opt-in rate?
It varies widely. Industry reports have commonly shown averages roughly in the 20 to 40 percent range among users who see the prompt, with large differences by category.
Can I restrict features if users decline tracking?
No. Apple's guidelines prohibit restricting functionality for users who decline tracking.
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Primary sources
Platform capabilities and limits can change. Verify current requirements in these official resources:
