Use Spam-Blocking Apps

Of course, the Call Blocking & Identification feature won’t work if you don’t have any good apps installed on your iPhone. So you’ll need to pick one or two to help you block those annoying spam calls.
There are many spam-blocking apps available on the App Store, so we’ll only recommend a few that you might want to try.
RoboKiller is another popular option. What’s cool about this app is that when it detects a spam call, it redirects the phone call to an answering robot so that they’ll learn not to call you again. Plus, what better way to spook spam callers than with Ice T answering your spam calls.
Robo Shield is considered one of the best apps on the App Store to block and filter spam calls on iPhone. It’s pretty easy to use, and it basically holds your hand the entire setup process, so you don’t have to worry about it later.
Truecaller is an amazing and easy-to-use app as well. All you need to do is set it up and forget about it. What makes this an amazing choice is that it’s free to use and considered one of the best in the market.
What’s great about this app is that it has a long list of possible spam calls, and it’ll immediately block them on your iPhone so you won’t get bothered. Of course, as you can guess from the name, this app is exclusive to AT&T users.
Just like the previous app, this is a great app for T-Mobile users. It’s got a long list of possible spam calls, and it’ll automatically block them.
It’s worth noting that Apple says the apps you use won’t have access to any information about your incoming calls, and they’ll only help you block and filter your incoming phone calls.