TLDR: If you use regular push notifications (even for legitimate purposes like keeping up-to-date info in the app) then you can tell when someone uninstalls you

TLDR: If you use regular push notifications (even for legitimate purposes like keeping up-to-date info in the app) then you can tell when someone uninstalls your app. If you wanted, you could then market to that person. True, but this doesn't bother me much, and I'm usually a privacy maven.