For iPhone, if you are logged in with the same account on both the website and your app, you will be able to import your JibJab.com faces to the iOS mobile app.
To do this, click the head in the lower center of the main screen. There, you will see a button which says 'Import.' Click the face you want, and it will be imported!
Android devices will have this feature soon. For now, you'll need to create new heads.