IOS - How to disable push notification at logout?

Question

My app registers the account at login in my server to enable push notification for a chat. Yet I haven't implemented yet the unregistration of the account at logout, so in this moment if I do the login with 2 accounts in the same device it can take the notification of both the accounts. At the same time, my notification center has a POST service which unregisters the 'login_name+ device token' from receive notification center. Where should I call it? Do I have to use unregisterForRemoteNotifications? I just want to unregister the account+Device token from push notification, not to disable the entire app notification forever.

Can I save my device token on didRegisterForRemoteNotificationsWithDeviceToken function like

 $ [[NSUserDefaults standardUserDefaults] setObject:hexToken forKey:DEVICE_KEY];

and then, at logout, call my POST function "removeDeviceToken" like

  NSString *deviceToken = [userDefaults objectForKey:DEVICE_KEY];
    if(deviceToken != NULL){
       [self.engine removeDeviceToken:deviceToken];
     }

Answer 1

In general it is a bad idea to unregisterForRemoteNotifications after logout and reregister after login. The reason is simple: if the user logins with another account and you don't specifically check for token overlapping in server, the user will start receiving double notifications.