It's gotten to the point with spamming phone calls here on the West Coast of Canada that I'd like to set up my iphone to automatically send any caller who's not in my contact list to voice mail. Is there any way to do this?
You can use "Do not disturb" mode judiciously. You can set the DND period to be effectively 24 hours, and add a contact group to the list of people who you will accept calls from. That works well for me. If someone calls you a second time, they will be allowed through - which works because the spammers generally only try once.
I agree that spamming has become downright silly.
Check with your carrier...they may have the ability to auto-block known robo caller numbers.
The problem I've been experiencing is that they spoof the number they're calling from and it's always different.