The documentation for ExtentChanged states that a developer should make sure that the data is available from the local map cache.
"Once the map extent changes, it's recommended that you (as a developer) make sure the data for the new extent is available either from local map cache (managed by MobileCache) or from ArcGIS Server (only in connected scenario)."
How do you see if the data in the new extent already exists in the map cache or not so you can know if you need to synchronize with the map server?
