That's exactly what you should do. In didRegisterForRemoteNotificationsWithDeviceToken you can store the device token locally, and then, when the user logs-in, you can send the device token with the user identifier to your server.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.