Apple has made changes in the upcoming iOS 15 where apps have to categorize their notifications into categories like “marketing” and functional categories. Users can then use the more granular controls to block notification categories either for all apps or app by app. This can also be mapped into the new Focus modes where users can setup different modes such a “work”, “sleep”, “driving”, etc. Different apps can be allowed or blocked in different focus modes.

https://techcrunch.com/2021/06/07/apple-refines-ios-15-notif...

https://9to5mac.com/2021/06/09/how-to-use-iphone-focus-mode-...

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