(BBC News) Police have urged everyone to download a smartphone app they say has already saved several lives. What is it and how does it work?
Kicked. Converged. Soccer.
These three randomly chosen words saved Jess Tinsley and her friends after they got lost in a forest on a dark, wet night.
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They had planned a five-mile circular stroll through the 4,900 acre (2,000 hectare) woodland Hamsterley Forest, in County Durham, on Sunday evening, but after three hours they were hopelessly lost.
"We were in a field and had no idea where we were," the 24-year-old care worker from Newton Aycliffe said.