The difficulty is, some people don’t keep their Fb profile up to date, and should have changed their cellphone number since entering it on Facebook. Also, it can be annoying to have your iOS device’s Mail app default to a buddy’s @facebook.com email address quite than the one they use most often, akin to Gmail or Yahoo.
Thankfully, as long as you haven’t tapped the replace button manually, it’s simple to remove all Facebook contact data from your iPhone and iPad.
If you signed into Fb in your gadget’s Settings menu (underneath iOS 6), contact info wasn’t actually written into your iPhone’s Contacts app. It merely subscribed you to the listing of contact info from Fb which was seen inside the Contacts app and different apps (resembling Mail) on your device.
To show off Facebook contacts, merely return to the Settings app, scroll down to Fb, tap it, then search for a section heading: Allow These Apps To Use Your Account. You will see Contacts on this list; all it's essential do is slide the switch to Off.