PulsePoint is an app that links those who know CPR with those who need it, "enabling citizen superheroes," as the product website claims.

Let's say you're with your husband and he starts having chest pain. You dial 9-1-1 and while you wait for paramedics, a neighbor comes over to help with an automated external defibrillator (AED).

According to KXLY in Spokane, Wash. a baby's life was saved in a scenario similar to that last year. A one-month-old turned blue and just after 9-1-1 was called, help arrived - in the form of a volunteer EMT who happened to work in a garage two blocks away. He received an alert on his phone with the address of the store where the baby was. The infant was kept alive before paramedics arrived.

Nancy Capelle of Wilton, Conn. celebrated her 40th birthday. A week later, she ran a 5K race. Just hours after the race, Capelle had a heart attack in her home, according to Smithsonian Magazine.

"Because I did not need open heart surgery or placement of a stent, my physical recovery was quite rapid," Capelle told the magazine. "But, the emotional recovery will take the rest of my life. I view life quite simply now - life is whatever place of moment we are in. Life is not a race to somewhere else, some greater achievement, or continuous recognition from others or acquiring material objects - it is about making a difference in people's lives."

Capelle set out to make a difference by quitting her pharmaceutical career, volunteering for the American Heart Association and becoming an EMT. Her goal is to raise awareness about PulsePoint and bring the app that is used on the west coast of the U.S. to the east.

"I hope to help PulsePoint reach the East Coast," Capelle told Smithsonian Magazine. "It's doing well [in] the West, but the entire country needs to know about it. For PulsePoint to make a difference, there needs to be a critical mass that will download the app and respond when needed."

According to WebMD, sudden cardiac death (SCD) makes up half of all heart disease-related deaths. Of those stricken with SCD, less than 10 percent survive, and for every minute that passes, a person's chance of survival drops 10 percent. If CPR is administered within the first four minutes of an arrest, survival chances increase.

"The chances of professional rescuers being able to respond to a scene in less than four minutes are unrealistic," Capelle told Smithsonian Magazine. "We need to be ready, willing and able to take hands on action in a cardiac arrest situation. I am one of the less than 10 percent who have survived. I am one of the lucky ones and I want there to be many more people who are given a second chance at life."