With the latest iOS 6 update, all your iPhone using buddies around the world are going to start syncing their Contacts to their Facebook account, hoping to automate what can be a fairly tedious process. Unfortunately, if you haven’t set your Facebook account settings to get your real email address into the sync information, your friends are going to just get a useless @facebook.com email address attached to your contact on their iPhone, and no one wants that.
Fortunately, there’s a way to fix this problem, and make sure Facebook’s secret switch to their own branded email addresses in your Facebook contact information doesn’t go any farther than it already has.
Log into Facebook, first of all, and head to your profile by clicking on your name, just under the tiny square picture you’ve set to represent you. Scroll down to where you see Contact Info, and click on the Edit button to the right. You’ll need to re-enter your Facebook password again to confirm.
To the right of each of the email addresses you’ve added to Facebook, you’ll see a little downward-pointing triangle. Click it and set it to Shown on Timeline for all the real email addresses you’d like to be synced to your hypothetical friends, and Hidden from Timeline for the ones you don’t want synced, especially that @facebook.com one.
You can also set the privacy of each email to allow the public, only friends, only yourself, or a custom set of privacy guidelines for each email address. If you have an email address set to show on timeline but only to friends, only the people who are on Facebook as your Facebook friend will be able to pull the contact down. In theory, of course, since Facebook changes privacy stuff all the time.