When iOS 14 was released at WWDC, it said that it would introduce anti-tracking ads. If it finds that the app has built-in IDFA (Identifier for Advertisers), iOS will ask the user if it allows it to retrieve some of your behavior data.
However, because Facebook, a number of game companies, and advertising companies have expressed their utmost attention to relevant measures to Apple, because they will affect the effectiveness of advertising and significantly increase advertising costs by more than 50%.
Some developers said that recently Apple has postponed the "anti-tracking" function until 2021. Apple stated to the online media TechCruch that technology should be used to protect users' basic privacy rights, which means providing users with tools to let them understand that App/Website may share their data for advertising or analysis purposes. Through the "Anti-tracking" function of iOS 14, users can choose whether to accept tracking. However, in order to allow developers more time to make necessary amendments to Apps, Apple will postpone the launch of the "anti-tracking" function until next year.