Naked selfies: why factory reset won't erase your phone

If you don't want your pictures and data recovered, destroy your old phone, says security expert

Naked photos have been retrieved from a batch of second-hand phones whose owners thought had been completely erased. Security firm Avast studied a batch of Android phones and found that using "standard forensic security tools" they could retrieve pictures, phone numbers and other sensitive information even after the phones had been given a "factory reset".