I am sure everyone knows this, however if anyone does not...
There is a feature in Android that I love called "Send to voicemail" When adding or editing a contact, at the very bottom is an option to "send to voicemail"
I have issues with telemarketers
calling 10-15 times a day; everyday! And I'm on the do not call list. Well they call from the same 4 phone numbers, so I created a contact (can't put the name here) and added the 4 phone numbers, then selected "send to voicemail." Now everytime they call, my phone sends them away and I never get bothered again.
As a side feature, I also have Youmail
which allows me to select numbers and select the option for people with blocked numbers and names to hear my ditchmail; that means when my phone sends them to voicemail, they get a "The AT&T number you have dialed has been disconnected, error..." then youmail HANGS UP ON THEM
so they can't even leave a message
This also works well with Ex's and in-laws and telemarketers.