Not that I'm against using an app like this by any means, but according to the FCC...
"placing telemarketing calls to wireless phones is - and always has been - illegal in most cases."
That was going through my mind also. That was preceded by the same rule for fax machines. The basic idea was that telemarketers should never make a call that could cost the recipient money (paper and maybe toner for fax machines, airtime minutes for phones). Many just did it until they got caught. They probably made enough that they'd pay the fine as a cost of doing business.
I think one catch to the rule was the "prior business" clause, where if you've done prior business with someone, they can still make telemarketing calls to you. Someone trying to get you to upgrade your existing service, as one example. But to be honest, I haven't had that happen to me in 15 years, maybe more.
For my part, I have used Google numbers for many years (since it was introduced). My primary number that everyone uses, has followed me between a few carriers, and needless to say, quite a few people have it. One cool feature of Google Voice (which I would lose if I switched to Project Fi
) is that if you block a caller, Google will send out a "This number is no longer in service" message to the caller. These calls end up in your GV spam folder. I do have some repeat callers--they just call from another of their incoming lines, but eventually I get them all blocked.
I've also been on the Do Not Call lists.
Ultimately I should answer those calls. I should learn some Slavic language, or even Polish (both part of my heritage), and start babbling to them in those languages.