When you load Into the Dead on Facebook it will attempt to connect to your Facebook account.
By allowing this, the game will be able to save your progress.
If you have connected to Facebook on your mobile device(s) you should be able sync your progress with the Facebook version.
You should be given a choice between your Facebook/Device Profile and the Cloud. Select the profile you wish to use and it will become the default profile used by all devices (when connected to the internet).