I don't understand why something like this exists natively on phones.

If someone calls from an unknown number, they get some sort of captcha to prove that they are a human, or they matter is important.

For example, the message should say that, if you are geniune, then please call again after 1 minute..

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SchemaLoad an hour ago | parent | next [-]

ios added "Call screening" which asks unknown callers to explain who they are and what they want before it rings the receiver.

The tricky part for scammers is there is no good answer here, if you claim to be a plumber and the victim hasn't booked a plumber, they won't answer.

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craftkiller 2 hours ago | parent | prev [-]

That already exists, it's "voicemail". The scammers never leave a voice mail (idk why). If a real person is trying to reach you, they'll either leave a voice mail or text you after you don't pick up.

	▲	qsera 17 minutes ago \| parent \| next [-]
		But voicemail implies storing the audio somewhere, and that means cost. And at least in my country one should explicitly enable voicemail. I never could make it work for some reason.. And as far as I can see, it is not widely used. EDIT: Oh, I completely missed the fact that there can be a fake voicemail where the phone automatically answers and asks the caller to speak and record it and store the audio on the phone itself. Then the user can check such recorded messages later.. Did you mean something like that? I am really surprised that this is not common already...
	▲	obezyian 18 minutes ago \| parent \| prev \| next [-]
		This is country-specific, though. In my country, despite voicemail being available since the introduction of mobile phones decades ago, I am yet to hear of a single instance of anybody actually leaving a message.
	▲	b3ing 2 hours ago \| parent \| prev \| next [-]
		Many spammers leave a prerecorded voicemail, they call quickly from 2 numbers so they can slide into your voicemail instantly without ringing more than once
	▲	2postsperday 33 minutes ago \| parent \| prev [-]
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