The ability to see who is calling you right away without having to pick-up or answer the phone, this makes me so much less stressed when I'm in meetings or working at my desk. Also the number of people who reach out after they leave their voicemails! It's difficult for us to keep track of all our contacts and send them messages as well. However, we've started using callbackshunter again since it allows someone else within our organization to be able to take care of contacting these leads for us