Verizon customers who are fed up with robocalls have something to cheer about.

By the end of the month, Verizon expects to offer a free app that will block those unwanted calls.

The company already offers an app to block calls, but that one costs $2.99 a monthVerizon told Forbes it expects to have instructions on how to download the free app by the end of the month.

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The number of robocalls grew by 325 percent worldwide last year, according to a Global Robocall Radar Report. In the United States, users received an average of seven spam calls per month, according to the report.

To combat this, Verizon will use authentication technology called SHAKEN/STIR, which will help to verify if the phone number on the caller ID is the same number that made the call.

AT&T and Comcast also announced they will use the SHAKEN/STIR for their customers.

SHAKEN stands for “Signature-based Handling of Asserted information using toKENs.” STIR stands for “Secure Telephone Identity Revisited.”

Not a Verizon customer? Nomorobo and RoboKiller are third-party apps that offer a free trial period. After that, both ask for a monthly fee.

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