Limit Ad Tracking (LAT) is a privacy feature on Apple iOS devices that allows users to opt out of personalized advertising. When LAT is turned on, Apple restricts advertisers and app developers from accessing the Identifier for Advertisers (IDFA), which is a unique code assigned to each device that enables ad personalization and performance measurement.
Instead of sharing a usable IDFA, the system replaces it with a string of zeros, making the device anonymous for advertising purposes. This means that advertisers cannot track user behavior or serve tailored ads based on individual activity.
Before Apple’s App Tracking Transparency (ATT) framework was introduced in iOS 14, LAT was the main way for users to limit data sharing with advertisers.
When a user enabled LAT:
With the release of iOS 14 and later, LAT was replaced by the ATT prompt, where users explicitly choose whether to allow tracking when opening an app for the first time.
For Users
LAT is a simple way for users to protect their privacy and reduce unwanted tracking. By turning on LAT, users gain:
For Marketers and App Developers
While beneficial for privacy, LAT has changed how marketers approach attribution and campaign optimization.
Starting with iOS 14, Apple replaced LAT with the App Tracking Transparency (ATT) framework. Now, every app must ask users for permission to track their data across apps and websites.
If a user selects “Ask App Not to Track,” the result is essentially the same as enabling LAT: no IDFA is shared, and personalized ads are disabled.
This shift reflects Apple’s broader focus on user consent and data privacy, giving individuals more control over how their data is collected and used in the advertising ecosystem.
Before ATT, fraudsters sometimes enabled LAT to disguise fake installs or spoof device identities. By doing this, they made it difficult for measurement providers to identify legitimate traffic, creating false attribution data.
To counter this, many mobile measurement partners (MMPs) developed techniques to flag suspicious LAT-enabled traffic and differentiate between genuine privacy preferences and fraudulent activity.
No. LAT does not remove ads entirely. It simply prevents personalized ads. Users will still see ads, but they will be more generic.
When LAT is enabled, your IDFA becomes a string of zeros, meaning advertisers cannot identify or track your device.
Not exactly. LAT was replaced by the App Tracking Transparency (ATT) system starting in iOS 14, which provides the same outcome through user permission prompts.
No. Apple’s policies strictly prohibit apps from bypassing these privacy controls. Violating them can result in app removal from the App Store.
LAT limits the ability to measure campaign success and retarget users accurately. However, it also encourages marketers to invest in privacy-first measurement methods, like aggregated or probabilistic attribution.