SAN FRANCISCO -- Its forthcoming iPhone might be getting all the attention, but Apple Inc. returned to its computer roots yesterday, showing off a new version of its PC operating system that emphasizes search and multimedia functions and promises to be easier to use than ever.
At a conference for software developers here, Apple Chief Executive Officer Steven P. Jobs also announced moves aimed at boosting the reach and relevance of its Safari Internet browser.
Apple released a beta version of Safari that can run on rival Microsoft Corp.'s XP and Vista computer operating systems. It plans to make a free, final Windows version of Safari available by download in October.
Jobs also announced that Apple will allow third-party software developers to create programs for the iPhone based on the so-called "Web 2.0" computer code standards at the core of Safari.
The iPhone will go on sale beginning June 29 at 6 p.m. local times everywhere, Jobs and Apple officials said.
Third-party software developers and others had worried they wouldn't be able to write applications such as games or sports information services for the iPhone. Apple and partner AT&T; Inc., meanwhile, had worried that opening iPhone up to outside developers could compromise its security and reliability.
By basing third-party applications on Web standards and including Safari on the iPhone, "we've come up with a very sweet solution," Jobs told about 5,000 attendees at the Apple Worldwide Developer Conference.
Many Apple users rave about Safari. But Jobs acknowledged that Safari has only about 5 percent of the Web browser market, trailing the 15 percent for Mozilla's Firefox and well behind the dominant 78 percent of Microsoft's Internet Explorer, which is included in Windows.
Creating a version of Safari for Windows and putting it on iPhone won't push Apple to the forefront of the browser market, but it could improve its position, said Van Baker, an analyst for technology research firm Gartner Inc.
"Even if [Apple] only gets a little bigger market share, it would be pretty significant growth," Baker said.
Expanding Safari's base of users could be important as Apple continues pushing into Web-based services - not only with computers and the iPhone, but also with new devices such as its Apple TV system that links televisions with computers and the Internet.
Published reports say Apple is working with major Hollywood studios to build an Internet-based movie rental service that would be a direct challenge to cable and satellite companies as well as to rental companies such as Blockbuster Inc. and Netflix. Recently, Apple and Google Inc. agreed to make videos on Google's YouTube site available through Apple TV.
Jobs didn't mention any movie plans yesterday. He spent most of his 90-minute keynote session showing off some features behind Leopard, the new version of Apple's OS X computer operating system. The software is scheduled to go on sale in October for $129.
Apple shares fell 3.45 percent yesterday on the Nasdaq stock market, closing at $120.19.