Apple unveils multitasking iPhone operating system

SAN FRANCISCO, April 8 (Xinhua) -- Apple Inc. on Thursday unveils a multitasking operating system iPhone OS 4 for its iPhone, iPod Touch and iPad devices.

Apple Inc. on Thursday unveils a multitasking operating system iPhone  OS 4 for its iPhone, iPod Touch and iPad devices.

"iPhone OS 4 is the fourth major release of the world's most advanced mobile operating system. We're delivering over 100 new features, including multitasking, folders, a unified inbox, deeper Enterprise support, and an iPhone version of our iBooks reader and online iBookstore," said Apple CEO Steve Jobs at a media event at its headquarters in Cupertino, California, according to the company's press release.

So far, iPhone only permits multitasking within its own programs. The iPhone OS 4 will enable users to seamlessly switch among all the softwares, including the ones from third party.

The new system will be available as a free software update to iPhone and iPod touch users this summer and a version of iPhone OS 4 will be coming to iPad this Fall.

Jobs also introduced a unified inbox for all e-mail accounts, allowing users to see messages from all their email accounts displayed together in a single inbox.

Meanwhile, Jobs said at the event that Apple has sold 450,000 iPad since its debut on Saturday and iPad owners have downloaded 600,000 digital books and 3.5 million applications for the new device.

Users had also downloaded more than 4 billion applications for the iPhone, he said.

On Monday, Apple announced that it sold over 300,000 iPads in the United States as of midnight Saturday, April 3.