You're right - the app sandbox model in iOS prevents inter-app communication of notifications, and there is no iOS equivalent to the Android ListenerNotificationService API.
Android 15/16 does allow you to control notifications even lower, at the level of notification category, but indeed the app must have chosen to use them.
Most apps that are in need of notification control either:
a) bundle everything in one category, from critical notifications without which the app can't fulfill its purpose to "HEY YOU HAVEN'T USED ME IN A DAY, USE ME NOW" spam
b) create a new category for spam every time they feel enough users have turned off the previous one, which is often
It has genuine use-cases such as this DoNotNotify app, but could easily be misused - e.g. malware intercepting a wallet OTP notification and forwarding it to the attacker.
Access to the API is controlled by a specific permission which users have to explicitly enable in "Special app access".
Another legitimate use case are e.g. Event Reminder, which intercept my calendar notifications and turn them into full screen alarms.
My distracted ADHD brain misses event notifications just too often, but with this app, even I my phone is in another room, I get reminded of that meeting, in time.
I can see why they changed the title! I wonder how many sales has Kanye West nade on account of his controversial views? He fills an unusual niche in the music industry.
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