Apple set to unveil new iPhone OS

Apple has extended invitations to an unveiling of the next generation operating system for its hit smartphone, the iPhone.

Apple said it would offer a "sneak peek" of the latest iPhone operating system at an invitation-only event at company headquarters in Cupertino, California.

"Get a sneak peek into the future of iPhone OS," the invitation said.

Apple released the iPhone in 2007. It sold 8.7 million iPhones in the last quarter of its financial year, up 100 per cent from a year ago. The unveiling of the latest software comes on the heels of Apple's launch of its eagerly anticipated iPad tablet computer.