iBlacklist is the best firewall for calls and SMS/MMS available for the iPhone. It ables you to select from who you want to receive calls and hide messages. It also removes the sms popup preview protecting your privacy, has parental control mode by blocking outgoing calls, can be fully scheduled and many other features. Try it , you''ll love it. Works on any iPhone model running any firmware version !!! PLEASE RESTART YOUR DEVICE AFTER INSTALL. REBOOT IF YOU ARE ON IOS4.