Update 2 (09/16/2021 @ 1:44 PM ET): You can now delete your advertising ID in Google Play Services. Click here for more information. The article, as published on June 3, 2021, is preserved below.

Google Play Services generates an advertising ID for all users who opt-in for ad personalization. This ID not only helps Google push relevant ads to users, but it also comes in handy for analytics and fraud prevention. When you turn off ad personalization on your account, Google stops using your advertising ID to push personalized ads, but it still maintains it for other purposes. However, that's set to change soon.

Currently, you can opt out of personalized ads by heading to Settings > Google > Ads or Settings > Privacy > Advanced > Ads on your Android device. Once you do so, Google Play Services will stop pushing personalized ad recommendations to your device, but apps on your phone will still be able to see the advertising ID. But a recent update on the Play Console Help page reveals that Google Play Services will soon delete the advertising ID when you opt out of interest-based advertising. The update states: "Starting in late 2021, when a user opts out of interest-based advertising or ads personalization, the advertising identifier will not be available. You will receive a string of zeros in place of the identifier."

After this change goes live, apps on your phone will see a string of zeroes instead of your advertising ID if you disable personalized ads. Google Play Services will also alert all apps that have access to your advertising ID and related data, so that any existing data can be deleted. In a notice shared by developer kdrag0n, Google further reveals that "This Google Play services phased rollout will affect apps running on Android 12 devices starting late 2021 and will expand to affect apps running on devices that support Google Play in early 2022. In July, we will provide more details and an alternate solution to support essential use cases such as analytics and fraud prevention."

At the moment, we don't have any information about the alternate solution that Google will introduce for analytics and fraud prevention. We'll update this post as soon as we learn more.

Thanks to developer kdrag0n for the tip!


Update 1: More details shared during July 2021 policy update

In the company's latest PolicyBytes video outlining the upcoming policy changes on Google Play, Google shared more details about what's happening to the advertising ID and its replacement for analytics and fraud prevention.

For starters, Google showed off what the option to delete your advertising ID will look like, a feature that will roll out to Android 12 devices via a Google Play Services update later this year.

Deleting your advertising ID on Android 12

The company also updated its support page on the Advertising ID with some new information. For any developers that need to be notified when a user deletes their advertising ID, Google is letting you sign up for the notification system here. Google also says that apps updating their target API level to 31 will need to declare the following permission in their manifest to query the advertising ID:

        <uses-permission android:name="com.google.android.gms.permission.AD_ID"/>
    

Some SDKs may already declare this permission, but it should be noted that the Families Policy prohibits the use of the advertising ID. In that case, you must prevent the permission from being merged into your app by including this element in your manifest:

        <uses-permission android:name="com.google.android.gms.permission.AD_ID" tools:node="remove"/>
    

Next, Google has shared some details on the alternate solution for essential use cases such as analytics and fraud prevention. Called app set ID, this ID is a unique identifier for all apps by the same developer on the device. Google calls this a "privacy-friendly option" to correlate usage or actions across a set of apps owned by your organization, and it must not be used for ads personalization or ads measurement, be connected to any Android identifiers or any personal and sensitive data for advertising purposes, and its collection must be disclosed to the user in a "legally adequate privacy notification, including your privacy policy."

App set ID SDK

The app set ID SDK will return an ID unique to the calling app itself if the app was installed from a source other than Google Play, if Google Play Services was unable to determine an app's developer account, or if the app was installed on a device without Play Services installed. The app set ID is cleared automatically if the API hasn't been accessed by the group of apps sharing the same ID for over 13 month, if the last app from a given set of apps is uninstalled, or if the user factory resets the device. The developer preview of this feature is now live, though Google warns that due to the potential for changes, the app set ID API shouldn't be used in production apps.

For more information, read the full developer program policy update announced today or watch the "PolicyBytes" video embedded below which summarizes the most significant changes.


Update 2: Now rolling out

Google Play Services is now rolling out the ability to delete your device's advertising ID, provided your device is running Android 12. One of our tipsters, @panduu221 on Twitter, told us they now have this feature. We checked our own Android 12 device and confirmed that the new "delete advertising ID" page is now visible. The roll out of this feature is likely controlled by a server-side flag, but for what it's worth, our device has version 21.36.14 of the Google Play Services app.