By Stephanie Stahl

PHILADELPHIA (CBS) — Two people have come forward with reports of how their smart watches kept them alive.

Smart watches can track everything from steps to sleep to calories burned, some provide heart-rate monitors which can detect life threatening situations.

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William Monzidelis was at work at his family’s bowling alley when he started to feel faint. In the bathroom, he found he was losing blood. That’s when his apple watch started sending alerts.

“I was getting notifications from my watch telling me that I need to seek medical attention immediately,” William said. “My heart rate is going too high and too low, numbers that I’ve never had in my life.”

His mother Nancy took one look at him, and knew something was wrong. They barely made it to the hospital.

“He started shaking his head, started projectile vomiting blood out of his mouth, his nose, whatever. Then, he passed out,” Nancy recalled.

William turned out to have a perforated stomach ulcer that was hemorrhaging.

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William is recovering, thanks to his timely reaction to his smart watch. Doctors told his mother if he hadn’t gone to the hospital when he did, he would have died within hours.

Deanna Recktenwald was in church when her smart watch sent an alert. Her heart rate was spiking.

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The teenager rushed to a hospital, where doctors diagnosed her with chronic kidney disease.

“It’s crazy how this watch led me to the hospital and helped me with that. I’m so grateful for that,” Recktenwalk said.

Apple’s CEO Tim Cook got wind of her story and responded with a tweet:”Stories like Deanna’s inspire us to dream bigger and push harder every day.”

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Experts say while smart watches can provide potentially life saving information .. They can also give false indicators .. So people should use them with caution and always in consultation with a doctor

Stephanie Stahl