Totally and completely useless.  What's the motivation of Verizon to allow robocalls in the first place?  Clearly the technology exists to block them at the source, why place a cost burden on users?

With the verizon call filter app and nomorobo I still get a dozen calls a day, most from the area code my phone is in  - - I now live 1800 miles away, so they're clearly spam.