Facebook introudces a new function ( switchboard ). However, this function can enclose your personal mobile number on your friends’ account.
1) First, login to your personal account and select Edit friends on your right hand side.
2) Click Phonebook on your left hand side. You can review your friends' personal phone number.
Please follow the steps as below to hide your personal phone number.
1) Go to Privacy Settings.
2) Please click on Custom on your right hand side.
3) Select Mobile phone section.
4) Set up the visibility as Only me.
