July 28, 2014
Gets whether the application instance was preserved.
Assembly: Microsoft.Phone (in Microsoft.Phone.dll)
When an application is deactivated, it is typically put into a dormant state. In this state, although no code is executed, the application state is preserved intact in memory. When an application is activated from being in a dormant state, it resumes automatically and does not need to reestablish its state. In the Activated event, the IsApplicationInstancePreserved property will be true if the application has returned from the dormant state and can resume immediately.
It is possible for an application to be tombstoned after being placed into a dormant state. In this case, the application is not stored in memory, although you can store state information in the application and page State dictionaries. When an application is activated after being tombstoned, the IsApplicationInstancePreserved property will is false, and the application will need to re-create its previous state. For more information, see App activation and deactivation for Windows Phone 8.