Opt out of ad tracking on iOS devices

Apple uses data collected from your iOS device along with an identifier associated with your Apple ID to send you interest based ads. Some ad tracking in iOS is also location based. When you sign in with an Apple ID on an iPhone, iPod touch, iPad or Apple TV, Apple reads your advertising identifier so that its advertising system can track you across apps. Fortunately, you can opt out of this if you wish. (Learn more about Apple’s advertising and privacy policies here.)

If you want to opt out of these interest-based ads, you can choose to turn on the Limit Ad Tracking setting on your iPhone, iPad, iPod touch, and Apple TV. You can also turn off Apple’s location-based ads on your iPhone, iPad, and iPod touch.

Turn Off Ad Tracking in iOS

• Go to Settings > Privacy > Advertising.
• Turn on Limit Ad Tracking.

Turn Off Location Based Ad Tracking in iOS

• Go to Settings > Privacy > Location Services > System Services.
• Turn off Location-Based Apple Ads.

Turn Off Ad Tracking in tvOS

• Go to Settings > General > Privacy.
• Turn on Limit Ad Tracking.

Additional Information:

From FTP.org:

In iOS 9 and previous versions, selecting “Limit Ad Tracking” meant that the OS would send a “flag”  indicating that that user had enabled the Limit Ad Tracking feature. Upon collecting this flag, developers were required under the Apple Developer Terms to not allow use of  the identifier for “targeted” advertising. Most ad networks treated this flag as a user request to opt-out of “behavioral advertising” or “interest based advertising.” Some ad networks continued to target ads based on location or continued to use the ad to help enable cross-device tracking. Other companies treated the flag as a broader opt-out of any targeting and tracking. Apple specifically permitted companies to continue to use the ID for certain limited other uses when Limit ad Tracking was enabled, including “frequency capping, attribution, conversion events, estimating the number of unique users, advertising fraud detection, and debugging.” Beginning in iOS 10, when a user enables “Limit Ad Tracking,” the OS will send along the advertising identifier with a new value of “00000000-0000-0000-0000-000000000000.” This will more effectively ensure that users are no longer targeted or tracked by many ad networks across sites. or over time. But it will also prevent the previously permitted “frequency capping, attribution, conversion events, estimating the number of unique users, advertising fraud detection, and debugging” uses of this ID.

According to the iOS Developer’s Library Ad Support,

This class is expected to be used by developers who are implementing a system for serving ads. These organizations typically provide app developers with the code that interacts with this class. App developers may need to link against the Ad Support framework to use that code, but they should not need to interact with the ASIdentifierManager class directly.

To get the advertising identifier:

1. Get a reference to the shared instance of this class using the shared() method.
2. Check whether advertising tracking is limited using the isAdvertisingTrackingEnabledproperty.
3. Get the advertising identifier using the advertisingIdentifier property (note that when ad tracking is limited, the value of the advertising identifier is 00000000-0000-0000-0000-000000000000).