"In New York City, robberies and grand larcenies from a person involving Apple products dropped 19% and 29%, respectively, in the first five months of this year, compared with a year earlier. In San Francisco, iPhone robberies declined 38%. In London, Apple thefts declined 24%. The statistics were compiled by New York Attorney General Eric Schneiderman.
The declines followed Apple's introduction last fall of an Activation Lock in the latest version of its mobile operating system. The feature allows the owner of a stolen device to remotely deactivate a phone, rendering it nearly useless to thieves.
Apple took this decision Under heavy pressure by the NY prosecutor general and police who were complaining of the enormous workload by stolen Iphones. Some anecdoctical evidence says that thiefs are now rather looking for other phones but the other phone companies have decided to develop also a kill switch.
This doesn't mean that the evidence is conclusive but it is always better than nothing and it gives the possibility for the victim to try to block access to his data.