How can I block calls from the "Unknown" caller? I have iOS 7 on an iPhone 4S. Does any other version of the iPhone offer this ability?
I've checked the question Call blocking for iPhone?, but it doesn't seem to work for "Unknown" callers.
I found the following question: Cannot answer unknown calls on my new iPhone 4S.
I want to do the opposite. I want to stop unknown callers from coming up on the phone, and I would rather not know that they are calling.