Apple’s privacy push continues, as Apple just killed some uninstall tracking in iOS 15 beta 4. Most significant app developers track app uninstalls via silent push notifications: push notifications sent to phones with zero payload. They’ll never show up on a device, but failure indicates that someone who installed your app has since deleted it.
From my post on Singular’s blog:
Background push notifications to with empty payloads never show up on a user’s device if your app is still present and installed, but they do verify the app’s installed status via the Apple Push Notification Service. Notifications on iOS don’t go directly from your servers to a user’s device: they go to a centralized Apple service and then are distributed to the device. That’s both a security and a usability feature for iOS, so iPhone and iPad owners don’t get blitzed with messages, and so that messages can be delivered to offline devices when they come back online. The Android equivalent is Google Cloud Messaging.
But Apple’s just made a privacy change: background pushes will only be delivered if the app has been used in the foreground in the past few weeks.