The Explorer doesn't allow SyncApps, for some strange reason. Why wasn't this added in the recently released update? Every other car seems to have it...
"SYNC AppLink is available on 2012 SYNC-equipped Ford Expedition, F-150, Fiesta, Fusion, Mustang and Super Duty; and the 2012 Lincoln MKZ and Navigator.
SYNC AppLink is also available as a software update for the North American 2011 Ford Fiesta."