Apple has delayed the implementation of new privacy measures designed to stop apps and websites tracking people online without their consent.
The changes also mean app will have to ask a user’s permission to access the ad-tracking ID on an iPhone or iPad.
The measures were due to arrive in the latest iOS 14 update in the autumn.
But Apple said the changes were being delayed until the start of 2021 to give app developers and websites more time to adapt their services.
Facebook has warned that Apple’s privacy plan could make one of its advertising tools “so ineffective on iOS 14 that it may not make sense to offer it on iOS 14”.
The social network says it will no longer collect users’ ad-tracking IDs on iOS 14, and that Apple’s plan had forced it to make that decision.