The introduction of kill switches that render stolen or lost devices useless has been credited with a dramatic drop in smartphone thefts around the globe, with robberies down 40 per cent in London.

The figures were released by Attoney General Eric Schneiderman, London Mayor Boris Johnson and San Francisco District Attorney George Gascón, three figures behind the “Secure Our Smartphones” initiative which has campaigned for the kill switch to be introduced. New York and San Francisco have also seen drops in phone thefts, with decreases of 16 per cent and 22 per cent respectively.

Apple introduced Activation Lock, its kill switch feature, in September 2013 following lobbying by the Secure Our Smartphones campaign. While initially an opt-in solution, there has been a steady decrease in thefts since its implementation, with iPhone robbers down 25 per cent in New York between January 2013 and December 2014.

During the same period, San Francisco saw a 27 per cent drop in overall smartphone thefts, and a 40 per cent decrease in stolen iPhones. The drops in smartphone crime in London have resulted in 20,000 fewer victims annually.

“After meeting with families who had lost loved ones to violent robberies targeting their smartphones, we decided to raise the alarm about smartphone theft and called on the industry to adopt kill switch technology,” said Schneiderman. “The huge drops in smartphone theft that have occurred since then are evidence that our strategy is working – fewer families are suffering, and people are safer in our cities and across the world.”