TORONTO -- It started with the loss of a phone and ended with the loss of a life.

Investigators are working to find those responsible for the death of an 18-year-old who was fatally shot as he was trying to find his lost cellphone -- an "extreme" case police said highlights the risks of using mobile-tracking apps.

Jeremy Cook left his cellphone in a taxi in London, Ont., on Sunday morning but was able to use an app to track the device's location to an address in the city's north end.

When he and a relative arrived at the location around 5:15 a.m., the app indicated the phone was with three men who were in a nearby car, police said.

What happened next is still being pieced together but police say that when Cook tried to retrieve his phone, the vehicle began to drive away, prompting him to grab on to the driver's side door. Shots were fired and Cook died from multiple wounds.

The vehicle with the three men -- who Cook didn't know -- sped away, collided with a fence and then a telephone pole, police said, before all three suspects fled the scene.

"It's certainly extreme," London Police Const. Ken Steeves told The Canadian Press. "No one ever would have predicted or even thought that a loss of life would have resulted from a loss of a phone."

As the investigation continues, police are urging anyone using an app to track down a lost or stolen phone to exert caution when they enter what might be a risky situation.

"The app itself is a great tool to have. Nobody could ever predict that what occurred was going to occur in that case," Steeves said. "But if you suspect there's any potential for violence at all, we certainly encourage people to contact police. We'd be more than happy to come out and investigate with the hopes of retrieving the phone."

Cook's case is thought to be the first time London police are dealing with a case of serious violence stemming from tracking down a waylaid phone, but Steeves said police may have helped others find their devices in the past through routine calls for assistance.

He noted, however, that the tracking application used by Cook wasn't what had resulted in his death.

"It wasn't the app that took away Jeremy's life, it was the individuals, which would be rare, who happened to be armed with a gun," he said.

Police are looking for three men aged 18 to 21 in connection with Cook's death. They are described as a black male wearing a white shirt with a black design, a black male with very short hair wearing a black jacket or shirt and a fitted hat, and a black male of slim build wearing a blue shirt and a black hat.

Cook's cellphone was found in the area where the suspects' vehicle was abandoned and is currently with police.

While Cook's death has stunned many who have heard his story, at least one mobile trend analyst says the motivation to track down a phone is understandable.

"Efforts by individuals to track their mobile devices and smart phones are linked to the extent to which we feel emotionally connected to our mobile device," said Sanjay Khanna, a mobile phones analyst with information technology market intelligence firm IDC Canada, who noted that phones now contain a significant amount of a person's data.

"Our attachment to our data is so strong that it might prompt people to not be as cautious as authorities might wish us to be."

Phones are often also costly, Khanna said, which adds to the motivation to get a device back.

That's not to say the use of tracking apps is always risky, said Khanna.

After leaving a phone in a restaurant or at a party, the apps can help owners retrieve their devices safely, he said.

"It could be pretty innocuous kinds of situations that people get into on a regular basis," he said. "The advice from police is typically not to go after your mobile device if that's going to put you in any sort of danger."