Police urge people to download an app which they say can save your life

Police have urged people to download a smartphone app in order to save lives.

What3words is a device which helps services such as the police and ambulances to track people to a specific location at a time of emergency.

Notts Police are one of those who have rolled out the programme as well as emergency services overseas.

It works by a unique three-word division of the map.

Developers have divided the world into 57 trillion squares, each measuring 3m by 3m and each having a unique, randomly assigned three-word address.

The randomly-assigned three-word address may not be immediately obvious.

For example, the door of 10 Downing Street is "slurs.this.shark", while the nearby area where the press congregate is known as "stage.pushy.nuns".

Founder Chris Sheldrick said he came up with the idea because of concerns over postcode system after growing up in rural Hertfordshire.

"Our postcode did not point to our house," he said.

"We got used to getting post meant for other people, or having to stand in the road to flag down delivery drivers."

He added: "I tried to get people to use longitude and latitude but that never caught on.

"It got me thinking, how can you compress 16 digits into something much more user friendly?

"I was speaking to a mathematician and we found there were enough combinations of three words for every location in the world."

The company started in 2013 and now employs more than 100 people at its base in west London.

One person whose life was saved by the system was Jess Tinsley in Co. Durham.

She used the words "Kicked, Converged, Soccer" when lost in a forest.

Together with her friends she saw a five-mile circular stroll suddenly became an emergency situation and after three hours they realised they were lost.

"We were in a field and had no idea where we were," the 24-year-old care worker told the BBC.

"It was absolutely horrendous."

After some time, they found a spot with phone signal and dialled 999.

"One of the first things the call-handler told us to do was download the what3words app," Ms Tinsley said.

"I had never heard of it."

Within a minute of its download, the police said they knew where the group was and the soaked and freezing walkers were swiftly found by the Teesdale and Weardale Search and Mountain Rescue Team.

"I have told everyone I know to download this app," Ms Tinsley said.

The app has even been adopted What3words by Mongolia for its postal service.

This article originally appeared on Yahoo