To activate Smart Blocking on an iPhone:
1. Open up your YouMail app
2.Make sure you are in your Messages or Hang-ups
3.Tap the caller you wish to block
4. Tap on the icon underneath the phone number
5. Tap Block
You have successfully blocked a caller with YouMail’s enhanced Smart Blocking! YouMail greets blocked callers with a message of your choice, such as a "This number has been disconnected."
Learn how to enable iPhone's built-in call blocking software.