Transcript for Could App 'ReThink' Prevent Cyberbullying?
A new weapon in the fight against cyberbullying. An app developed by an impressive teenager that aims to stop the bullying before it even starts. Alex Perez has that story. Reporter: For teen tech whiz Trisha, being a high school science nerd is actually kind of cool. She's traveled the world sharing her ideas even a headliner at Ted talks about the problem of cyberbullying. I'm passionate to stop it at the source before the damage is done. Reporter: But now she's got an app for that. Over the past two years the problem has been developing rethink. An app to make cyberbullies think twice before sending a hurtful text. It's able to detect when someone posts something offensive and alert that person and go, whoa. Hold on. Are you really sure you want to post that message? Reporter: The alert, a pop-up window on the screen. We're giving them a chance to rethink their position at which point they can either hit, you know, clear, maybe I do want to think about this or they can go ahead and decide that they want to post the message. Reporter: The app built with a growing database of trigger words and phrases that could be offensive and the sophisticated program is intuitive. Rethink is able to understand the difference between I hate Chicago's weather an I hate you because those are two different scenarios. Reporter: Her parents are both in computer science and started coding at age 10. The idea for rethink was born when she learned about 12-year-old Rebecca Sedgwick who committed suicide after being cyberbullied by two classmates. It led her to studies on the brain and the part that regulates impulse control is not fully developed in teenagers. The adolescent brain is like a car with no brakes so we don't think about what we're doing when we post something. Reporter: Pradahu tested it on 300 students with eye-opening results when the teenager gets an alert from rethink. The overall willingness to post an offensivemessage drops from 71% to 4%. Reporter: The research winning her a coveted spot as a Google science fair finalist. I think anything we can do to reinforce the bullies to check themselves and victims to possibly not be a victim we're moving forward. Reporter: Pradahu has no plans to profit from it. She says the app which is already available for android users will release an iOS version in the next few weeks. For "Good morning America," Alex Perez ABC news, Chicago. Wow. I'm telling you and I was just told up in the control room when using this app, teens, 93% will not then send that offensive tweet or message. 93% will change their find because of the app and they have a chance to think, rethink. Time to get it. Yeah, that's -- we can all use it. Yes. We could all use it.
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