In some cases when the App Badge is not displaying any information, it may be that the Notification Settings in iOS have this option turned off.
To allow application badges to display you want to open the iOS Settings application, then Notifications, then Informant and scroll down and select \"Badge App Icon\".
Additionally you will want to go into the Informant settings, general settings, application badge and check the application badge settings. Then check your Informant data to make sure that you have data that meets the badge criteria. If none of your data matches the badge criteria it will not be displayed.