Wish list grows for iPhone update

Apple Inc. will unveil an update to the software that powers both devices at an event today. IPhone owners and computer programmers who write applications for the popular smartphone have grumbled over limits to such multitasking. The matter may escalate as people with iPads, which have larger screens, try to use them in place of more powerful computers.

The iPhone already allows for some multitasking, but that is largely limited to Apple’s own programs. One of Apple’s recent commercials shows an iPhone user taking advantage of time spent on hold paying bills, checking e-mail, playing games, and then switching back to calling.

But Apple has yet to give users ways to seamlessly switch among all the software “apps’’ available from outside software companies, the way phones from rivals Palm Inc. and Google Inc. already do.

So an iPhone user wouldn’t be able to listen to music using the Pandora program and check a bank account online simultaneously, for example. In most cases, users must return to Apple’s home screen, effectively quitting the open program, before starting a new task.

That’s unacceptable to many users and software developers, and full multitasking remains high on many people’s wish lists. Because Apple’s new iPad runs the same software as the iPhone, changes would apply to that larger gadget as well. Some people have held off buying one because of its inability to run more than one program at a time.

But the reasons Apple is believed to be resistant to broader multitasking — worries about battery life, performance, and security — remain.

Ross Rubin, an analyst from NPD Group, said he believes those are still big issues for Apple, and he doesn’t believe full multitasking will be among the changes in the iPhone operating system to be announced at Apple’s Cupertino, Calif., headquarters today. Apple did not immediately answer requests for more information about its plans.

Apple has given software developers limited ways to work around the multitasking restrictions, such as allowing them to send very basic notifications nudging iPhone users to open an app for updated information.

The new version of the iPhone system, likely to be known as OS 4.0, probably won’t be available for a few months. Most of the changes would have immediate appeal to software developers, not regular users, said Charles Golvin, an analyst for Gartner Inc.