(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.
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These three randomly chosen words saved Jess Tinsley and her friends after they got lost in a forest on a dark, wet night.
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.