In 2006 several important events relating to mobile malware took place. Commercial Trojans created for Symbian began to steal money from mobile users accounts Malicious programs for standard (i.e. non-smartphone) mobile phones appeared. Asian hackers turned out to be the most prolific. Overall, their programs stood out in terms of the platforms targeted and the moves made towards the relatively uncharted realm of mobile technologies. At present, most new mobile malware is being created by just one or two people worldwide.”]
Source: https://securelist.com/kaspersky-security-bulletin-2006-mobile-malware/36129/