Use a Google Voice Number to Filter Out Non-Contact-List Calls

Google Voice's Screening feature allows you to configure your phone's reaction to calls from outside your contact list. Actions include sending directly to voicemail or asking for the caller's name. You can keep your normal phone number, or you could even get a whole new number! An alternative is Nomorobo for iOS, which compares a caller's number to known scammers/robocallers. However, it requires a paid subscription, unlike Google Voice.

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