Amazon is bad, but as others note, it’s insultingly transparent more than anything. But the worst in my recent history is Duolingo. Constant pestering to upgrade your subscription, fine, but once you do, it frequently “forgets” the subscription (through the App Store) and goes back to nagging you, only fixed by digging a few screens into the profile and tapping “restore purchases”. Bigger issue when your family is using it and doesn’t understand you’re already subscribed. Paid for two family subscriptions this way.