A person mad about robocalls smashing a smartphone with a hammer.
Illustration: Chris Philpot

Phone companies and others offer apps and devices designed to help reduce robocalls by blocking or identifying suspicious phone numbers that could be fraudulent. Those numbers could be those that Federal Trade Commission collects on a blacklist or that the artificial intelligence algorithms in the apps or devices have flagged as suspicious because of the sheer volume of calls they make.

Consumers who downloaded these apps and responded to a Consumer Reports nationally representative survey of 1,002 U.S. adults conducted in December 2018 said they work to varying degrees.

Here are some options to try.

More on Robocalls

Your Phone Carrier’s Anti-Robocall Service
Many cellular providers, including AT&T, Sprint, T-Mobile, U.S. Cellular, and Verizon, have services that alert you on your phone that an incoming call may be from a telemarketer, and detect and block calls from probable scammers. In certain cases, these services are free. For others, especially those that offer advanced security and control of calls, you’ll have to pay. AT&T, for example, offers a basic free service, AT&T Mobile Security & Call Protect, that consumers can enable by signing up on the telecom’s website. For $4 per month, AT&T offers Mobile Security & Call Protect Plus, which the company says also helps protect your data from mobile threats by providing a secure WiFi virtual private network (VPN). To find out what your carrier offers, sign in to its website and look for links referring to call security or call blocking.


Help end 'spoofed' robocalls! Demand phone companies put anti-robocall technology to work by signing our petition.
 

Call-Blocking Apps
Also available are third-party apps meant to block robocalls before they reach users. The apps can do this using the FTC blacklist as well as proprietary artificial intelligence technology that flags suspicious numbers, such as those that suddenly start to make thousands of calls. If your incoming calls are flagged by the app’s algorithm, they will, in theory, be blocked. Sometimes the apps allow users to block numbers or create a so-called whitelist of numbers to allow through. Widely used apps include Nomorobo, which costs $2 per month (free for landlines and available in partnership with certain telecom providers), as well as free apps such as Hiya, YouMail, Mr. Number, RoboKiller, and Truecaller. (Consumer Reports has not tested the cell-phone apps.)

It’s important for consumers to read and understand the app’s terms of service and privacy rules—as they should with any app downloaded from the internet. Some, such as Nomorobo, don’t require access to your contact list and other private information, but some of the free apps might.



Google’s Call Screen
Google has recently unveiled a new tool called Call Screen that is built into its Pixel 2, 2XL, 3, and 3XL smartphones. When you receive a call from any number, you can tap “screen call” on your home screen and have your Google Assistant screen the call. Google Assistant will answer the call for you and have caller identify herself and why she’s calling. When a caller responds, a real-time transcript of the response is displayed. If it’s someone you want to speak to, you can simply answer the call. If it’s a robocall, you can automatically report the call to Google as spam as well as log it or blacklist it locally on your device. The tool will then block the number from calling you in the future. The tool also lets you select a few canned responses, such as “I’ll call you back.” The new technology should eventually become available on other Android devices. Although this tool (and others like it) screens the call, it does not prevent the phone from ringing and interrupting you.

Landline Call Blockers
Solutions also exist for nondigital landlines (copper wire lines) and typically involve installing hardware between your phone and the telephone line. These devices come preloaded with numbers that will be blocked and that users need to update with unwanted numbers as they are received. These devices have a wide range of prices, from around $20 to more than $100.

Nomorobo offers a free robocall-blocking service for landlines, but it works only on newer digital phone lines and not old-school copper lines.

Editor’s Note: This article also appeared in the May 2019 issue of Consumer Reports magazine.