Apple has changed its App Store guidelines, granting apps the ability to send push notifications that contain advertising.
Originally, Apple banned apps from sending notifications to users that contained any form of advertising. Now, the company has altered its App Store guidelines, and now apps can send through push notifications that contain advertisements if the user agrees to it. Apple says that app developers can send marketing notifications when "customers have explicitly opted in to receive them."
This new change has opened the door for iPhone users to be spammed with advertisements from already downloaded apps. Apple doesn't specify if users will have to enable advertisement push notifications from already downloaded apps. An example of this could include Amazon sending push notifications for an upcoming sale. 9to5Mac also found that Apple has set its deadline for when 'Sign In with Apple' will be implemented. This feature is a replica of Google's single system sign-in that allows users to get into new apps quickly.