How can I get a notification from App Store or APNs when my iOS App gets uninstalled?
Also, if I send a push notification for the device where my App is uninstalled, what happens? Will Apple ban for such rogue Push notifications?
There isn't a way that your app will know if it is uninstalled. Also I do not believe there is anyway Apple will tell you if your app is uninstalled.
Apples Push Notification Service's FeedBack Service does provide a way to know if a device cannot receive a notification. However this does not guarantee that the device was uninstalled, only that it, for whatever reason, can not receive push notifications.
If a provider attempts to deliver a push notification to an application, but the application no longer exists on the device, the device reports that fact to Apple Push Notification Service. This situation often happens when the user has uninstalled the application. If a device reports failed-delivery attempts for an application, APNs needs some way to inform the provider so that it can refrain from sending notifications to that device. Doing this reduces unnecessary message overhead and improves overall system performance.
For this purpose Apple Push Notification Service includes a feedback service that APNs continually updates with a per-application list of devices for which there were failed-delivery attempts.
来源：https://stackoverflow.com/questions/12217603/iphone-app-uninstallation-notification