Apple ID for Advertisers

Apple's ID for Advertisers (IDFA) is a unique random device identifier which Apple generates and assigns to every device. It is intended to be used by advertisers to deliver personalized ads and attribute ad interactions for ad retargeting. Users can opt-out of IDFA via the "Limit Ad Tracking" (LAT) setting (and an estimated 20% do).[1] Starting with iOS 14.5, Apple plans to allow users to decide whether to opt-in or out of IDFA sharing on a per-app basis.[2]


Limit Ad TrackingEdit

In iOS 10, Apple introduced "Limit Ad Tracking" setting for users who do not wish to be tracked by advertising networks. If the setting is enabled the system returns a default all-zero id for that device. As of December 2020, it's estimated that approximately 20% of users turn on this setting.[1]

iOS 14Edit

In the spring of 2021, Apple plans to restrict access to IDFA and require websites and apps to obtain an explicit permission from users before being granted access to IDFA. As of January 2021, users and developers can test this change by installing a recent iOS 14 beta.[2]

In July 2020, Facebook stated that this transparency requirement will likely hurt their advertising targeting.[3] Facebook said that these changes "may render [their tracking] so ineffective on iOS 14 that it may not make sense to offer it on iOS 14" and Facebook apps on iOS 14, including Facebook, WhatsApp, Instagram, Messenger, and others will not collect IDFA on iOS 14.[4][5]

In early September, Apple postponed these restrictions until early 2021.[6]

In December 2020, Mozilla Foundation expressed support for Apple restricting access to IDFA and asked users to sign a petition to "help strengthen [Apple's] resolve to protect consumer privacy".[7]

On December 15, 2020, Facebook launched "Speak Up for Small Businesses" campaign against Apple. In this campaign, Facebook purchased full-page advertisements in newspapers and created a web page claiming Facebook tries to help small businesses. This campaign became controversial even within Facebook itself, because some employees thought Facebook was "trying to justify doing a bad thing by hiding behind people with a sympathetic message."[8]

On January 27, 2021, Google announced that when the new requirement goes into effect, a "handful" of Google apps will stop collecting IDFAs (and thus the apps will avoid displaying a prompt for allowing tracking user activity).[9]

On March 18, 2021, Facebook changed its stance. Facebook CEO, Mark Zuckerberg, claimed that these changes might even strengthen Facebook position "if Apple’s changes encourage more businesses to conduct more commerce on [Facebook's] platforms by making it harder for them to use their data in order to find the customers that would want to use their products outside of [Facebook's] platforms".[10]

On April 1, 2021, Apple App Store started rejecting apps which used Adjust SDK and attempted to circumvent App Tracking Transparency rules via device fingerprinting (collecting device and usage data to create a unique identifier in order to track the user).[11][12] On April 2, Adjust removed the offending code and app developers might pass App Store review after updating to the new Adjust SDK version.[13][14]

See alsoEdit


  1. ^ a b "Identifier for Advertisers (IDFA) | Meaning". Adjust GmbH. Retrieved 2020-12-25. roughly 20% of iOS users cannot be tracked using the IDFA because they have enabled LAT.
  2. ^ a b Statt, Nick (2021-01-28). "Apple's next iOS 14 beta will begin forcing developers to ask for permission to track you". The Verge. Retrieved 2021-01-29.
  3. ^ Rodriguez, Salvador (2020-07-30). "Facebook says Apple's iOS 14 changes could hurt its ad targeting". CNBC. Retrieved 2020-07-31.
  4. ^ Cox, Kate (2020-08-26). "iOS 14 privacy settings will tank ad targeting business, Facebook warns". Ars Technica. Retrieved 2020-08-27.
  5. ^ Wagner, Kurt (2020-08-26). "Facebook Says Apple's Changes to iOS Will Dramatically Hurt Ads". Bloomberg. Retrieved 2020-09-08.
  6. ^ Statt, Nick (3 September 2020). "Apple delays privacy feature that would let iPhone owners keep ad tracking at bay". The Verge. Retrieved 16 September 2020. CS1 maint: discouraged parameter (link)
  7. ^ "Mozilla Urges Users to Support Apple's Planned Anti-Tracking Changes: 'A Huge Win for Consumers'". MacRumors. Retrieved 2020-12-17.
  8. ^ "Facebook Says It's Standing Up Against Apple For Small Businesses. Some Of Its Employees Don't Believe It". BuzzFeed News. Retrieved 2020-12-25.
  9. ^ "Google to Stop Collecting Advertising Identifiers in iOS Apps in Response to iOS 14's Upcoming Tracking Prompt". MacRumors. Retrieved 2021-01-28.
  10. ^ Axon, Samuel (2021-03-19). "Zuckerberg: Facebook could be in "stronger position" after Apple tracking change". Ars Technica. Retrieved 2021-03-19.
  11. ^ Koetsier, John. "Apple Rejecting Apps With Fingerprinting Enabled As iOS 14 Privacy Enforcement Starts". Forbes. Retrieved 2021-04-03.
  12. ^ Axon, Samuel (2021-04-02). "New wave of App Store rejections suggests iOS 14.5, new iPad may be imminent". Ars Technica. Retrieved 2021-04-03.
  13. ^ "Version 4.28.0 by nonelse · Pull Request #526 · adjust/ios_sdk". GitHub. Retrieved 2021-04-04.
  14. ^ "Apple Now Rejecting App Updates That Defy iOS 14.5 App Tracking Transparency Rules". MacRumors. Retrieved 2021-04-04.