Apple previews iPhone OS 4, adds multitasking

Computerworld - Apple today previewed the next generation of its iPhone software, which will add over 100 new features, including the long-awaited multitasking, to the iPhone, iPod Touch and iPad.

CEO Steve Jobs took the stage at the company's Cupertino, Calif. headquarters to announce a developer preview and SDK (software development kit) for iPhone OS 4.0, both available immediately to application developers. The public will receive the update later this year.

iPhone and iPod Touch users will see iPhone OS 4 first -- this summer, said Jobs without naming a date -- but iPad users won't get it until this fall.

And not all iPhone owners will be able to access all the iPhone OS 4 features, he warned. Only the iPhone 3GS and the 32GB and 64GB models of the latest iPod Touch -- the latter was released last September -- will get multitasking, for example. Owners of earlier iPhones and iPod Touches, including 2008's iPhone 3G , will be left out in the multitasking cold. The iPhone 3G and second-gen iPod Touch, however, will be able to use other features of the update, although Jobs did not specify which ones.

During the 60-minute presentation, Jobs, Scott Forestall, Apple's senior vice president of iPhone software, and several iPhone developers touted the additions to the mobile operating system.

The star of today's preview was clearly multitasking, the ability to run multiple programs simultaneously. That functionality, missing from the current iPhone and iPad, has been at the top of users' wish lists for years, and the subject of intense speculation in the weeks leading up to today's event.

"Now, we weren't the first to this party, but we're going to be the best," said Jobs of multitasking." Just like cut and paste," he added, referring to the feature Apple added last year to the iPhone's operating system.

What took so long? "It's easy to do this in a way that drains battery life, and a way that reduces performance of the foreground app," Jobs argued. "If you don't do it right, your phone will feel sluggish. We figured out how to implement multitasking for third party apps and avoid those things. So that's what took so long."

As experts expected, Apple did not throw open the multitasking doors, letting just any developer add full-function multitasking to their applications. Instead, Apple added seven multitasking-specific APIs (application programming interfaces) to the iPhone OS 4 SDK.

Among the tasks that will be allowed to multitask, said Forestall, are audio play, voice over IP (VoIP), location services, task completion and what Apple called "fast application switching," which suspends an application, then lets a user resume at the point he or she left off.