Apple is late in delivering technology that would enable third-party iPhone applications to run in the background in order to immediately receive alerts, messages, and other content. But analysts say consumer demand for such features remains low, so the delay is unlikely to have an impact on the consumer electronics maker.

At last June's Worldwide Developers Conference, Apple chief executive Steve Jobs announced the push-notification system for the iPhone. While the service had been set to debut in September, it was removed from the beta version of the iPhone's firmware in August.

Jobs acknowledged to one customer that the feature was running late and said the company wanted to make sure it got the service right the first time, according to Apple enthusiast site MacRumors. In addition, the site said it has learned that Apple is considering an alternative that would let users select the apps that would run in the background. Such a feature could be available in the next major update of iPhone software.

Currently, only select Apple services, such as e-mail checks and music playback, are allowed to run continuously in the background. Third-party applications are automatically shut down once the user switches to a different function.

Analysts agree that extending the always-on capability to non-Apple services could significantly expand the usefulness of the iPhone. "It's the type of service that could create more interesting types of applications for the future," Michael Gartenberg, an independent analyst, told InformationWeek.

Users, for example, could receive news alerts, instant messages, or notifications when a friend is nearby. There's also marketing potential. For example, iPhone users, could opt in to have a business notify them when they're near a store where there's a sale going on.

Such services, however, aren't yet available in today's smartphones, which are just starting to incorporate the needed technology. Google's Android operating system has the capability, and the Palm Pre is expected to have it when it's released later this year. Smartphones running Windows Mobile also have the technology, but it's a "bit clumsy," Charles Golvin, analyst for Forrester Research, told InformationWeek.

Because such services are at a very early stage, Apple has time to fine-tune whatever it has planned. "It's important, but it's not critical today," Golvin said. "It's more important in the future."

That's because once people get used to their smartphones' current capabilities, such as Web browsing, e-mail, and games, they're likely to start looking for more uses for the devices.

"The demand from users today is relatively low, because they're still developing an understanding of the current range of capabilities," Golvin said. "But as users become more skilled, their expectations are raised."

Apple does not comment on future products or services, so iPhone fans will have to wait to see how well Apple delivers on its earlier promise. "We'll have to see how this ultimately is released and in what form, and whether developers can take advantage of it," Gartenberg said.