T-Mobile to start warning subscribers when an incoming call is a scam
If you are particularly allergic to scam, you can arrange to have such calls blocked before the notification even hits your screen. But keep in mind that the service could accidentally block legitimate calls, which is why you will have to opt in to support the spam blocking service.
According to T-Mobile, calls are compared to a list of "tens of thousands" of phone numbers used by scammers. And new numbers are added all of the time. Some of the new numbers used by scammers are detected by using common sense. If T-Mobile sees that a particular number is constantly hung up on within seconds of a call connecting, chances are that the call was placed by someone trying to pull the wool over T-Mobile customers' eyes. These call patterns are an important tool used to fight against scammers
On April 5th, those subscribed to the unlimited T-Mobile One plan can activate the warnings by dialing #662#. Eventually, all T-Mobile users will have access to this plan, including customers of pre-paid carrier MetroPCS (which is owned by T-Mobile). The service is free and might save you from losing a lot of money to a scam artist.