Apple warns iPhone users to update software

Apple is encouraging people to update their iPhones in light of new cybersecurity research that suggests that Russian intelligence, Chinese cybercriminals and other hackers have been using tools nicknamed DarkSword and Coruna to take over phones running older versions of the iOS operating system.The news has prompted worry from industry experts that while Apple enjoys a reputation for producing devices that are safer from hackers than other brands, versions running on older software can still be vulnerable to takeover. Which mobile form is the safest ?