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Google Voice comes with various functionalities that can help you to listen to the voicemails before even answering the calls, customize a ringtone for dedicated callers, routing a call, Voicemail transcripts, recording a call, get voicemail notifications via email or SMS, block a call, get conference calling, switching phone devices during a single call, and much more.

https://www.instanttfn.com/blog/how-does-google-voice-phone-number-work