Having A Heart Attack? This App Alerts Nearby Strangers Who Could Save Your Life

Volunteer heroes who know CPR sign up, and the app tells them when someone is in trouble.

If you dial 112 in Stockholm–the European equivalent of 911–and report a heart attack victim, it won’t take long for an ambulance to show up. But a volunteer might to get there first. A new app uses GPS to ping anyone from a network of thousands of CPR-trained “lifesavers” who happens to be in the neighborhood.


“In short, every second counts,” says Rasmus Sellberg, strategy director for Daytona, the Swedish digital agency that worked with medical researchers to develop the app. “Bystander CPR dramatically increases survival rates. It’s a matter of life or death.”

Each minute without treatment after a heart attack, someone’s chances of survival drop by 10%. In Stockholm, around 900 people have heart attacks outside hospitals each year, but only 90 survive; whether they make it is directly tied to how quickly someone reaches them to do CPR or use a defibrillator.

Researchers at Karolinska Institute first developed an early version of the system (called SMSlivräddare, or SMS Lifesavers) in 2010 in central Stockholm. Knowing that heart attack victims are up to three times more likely to survive with help from a trained bystander, they recruited volunteers and started sending texts and automatic calls to anyone in the group nearby. Not surprisingly, the system made it much more likely that a volunteer could reach a victim in time to help–especially because many heart attacks happen at home, out of sight of potential help from strangers.

The new app makes the system easier to use, with simple, obvious steps, and was designed along with the research team. “Most functionality was derived directly from the medical research results,” says Sellberg. The designers added a few features, like a “test alarm” that a volunteer can push to see what it’s like when they’ll actually get an alert. “The entire experience is very stressful, and we discovered a strong need among lifesavers to feel prepared,” he says.

The app gives directions to reach the victim, and once a volunteer arrives, it also gives basic instructions for CPR and a metronome to help the volunteer keep the perfect timing. If there’s a defibrillator nearby, some of the volunteers get instructions to bring it to the scene.


It’s the kind of app that could also be useful in places like the United States, where 38 people have a heart attack every hour, and less than half get help from bystanders.

About the author

Adele Peters is a staff writer at Fast Company who focuses on solutions to some of the world's largest problems, from climate change to homelessness. Previously, she worked with GOOD, BioLite, and the Sustainable Products and Solutions program at UC Berkeley.