It's stored on a per-user basis. Note "user" refers to the operating system user, not the logged in google account.
In versions of the platform lower than Android 8.0 (API level 26), a 64-bit number (expressed as a hexadecimal string) that is randomly generated when the user first sets up the device and should remain constant for the lifetime of the user's device. On devices that have multiple users, each user appears as a completely separate device, so the ANDROID_ID value is unique to each user.
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It's stored on a per-user basis. Note "user" refers to the operating system user, not the logged in google account.
https://developer.android.com/reference/android/provider/Set...