Updated

Robocalls, meet RoboKiller.

The winner of the 2015 Federal Trade Commission’s Robocalls: Humanity Strikes Back contest, RoboKiller is an app that smothers robocalls on landlines and mobile phones. Creators Ethan Garr and Bryan Moyles rely on universally available call forwarding to screen incoming calls, and use audio-fingerprint technology to determine if the call is from a human or a robot. “We’re about 98 percent effective,” says Garr.

You dial a simple code to forward calls to RoboKiller. When a call comes in, the system analyzes it for audio clues that identify whether the caller is a human or a robot—“chunks of silence, delays, how the sounds are made, how the sounds scale,” Garr explains. “All these details go into our algorithm, which weights them and scores the result as human or robot.”

Learn how to deal with the these annoying calls in "Rage Against Robocalls." And find out what works best against them in our robocall blocker review.

If the call is from a robot, Garr says, “we kill it and put it in our SpamBox.” (That’s RoboKiller’s term for a “honeypot,” an information system used by government, private and academic partners to lure, collect and analyze robocalls.)The SpamBox utilizes consumer-controlled whitelist and blacklist filtering and provides personalized setting options. RoboKiller also analyzes data to identify “legal” calls such as notifications of school closings or your pharmacy alerting you to a prescription refill. Consumers can access the SpamBox at any time to update their whitelist settings.

If the caller is human, the call is returned to your smartphone. “That’s the one requirement,” says Garr. While calls can be forwarded from any type of phone, he notes, “You need a smartphone” to receive the calls. In the future, though, consumers will be able to port their phone numbers to RoboKiller, so the call can be returned to a landline.

Garr and Moyles work for TelTech, a New Jersey-based app developer, whose TrapCall caller ID unmasking device helped protect consumers from this year’s notorious IRS phone scam. “We saw people get hurt from the IRS phone scam and we learned that robocalls were part of that problem. That’s where we came up with the genesis of the idea for RoboKiller,” Garr says.

RoboKiller is currently available in a free beta format for iPhones and Android phones. Garr and Moyles are donating their $25,000 prize money to a Kickstarter campaign to further develop RoboKiller. “What will make RoboKiller successful is people using it,” says Garr. “This has the potential to solve the problem of robocalls on a mass scale. We’re improving every day.”

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