Apple makes IDFA opt-in on app-by-app basis in iOS 14
Apple is expanding privacy protections in iOS 14 with a tweak to IDFA handling that makes it much more difficult for advertisers to track users.
The feature concerns Identifier for Advertisers (IDFA), a random device identifier tag that Apple assigns to a user's device. Advertisers have long used the feature to track aggregate data without revealing a person's identifiable information.
A new popup box asks users if they would like to give permission for an app to "track [them] across apps and websites owned by other companies" to deliver personalized ads. Previously, Apple users had the option to disable the IDFA, though the toggle was buried in the Settings app.
Apple made a related change in iOS 13 to curb location-based tracking by advertisers. Many users stopped apps from tracking their location, suggesting that something similar could happen for aggregate data.