Will iPhone Ring for Apple's Stock?

It's not just consumers who are waiting for Friday's iPhone release. Investors also have a big stake in it as well.

For most of the year, Apple's stock price has risen and fallen -- mostly risen -- on news of the iPhone. It's impossible to predict whether the long-awaited release of the phone will cause Apple's stock to shoot up or fall short, but it's more than likely to move the market.

Apple's stock started the year at $83.80 a share. It's now trading at $123. Most of that push came from the iPhone, which combines the company's popular iPod music player with a touch screen that lets users surf the Web and get e-mail.

When the iPhone was first announced on Jan. 9, Apple's stock jumped 8.3 percent. But some other phonemakers didn't fare so well. Palm, maker of the Treo smart phone, fell 5.6 percent, and Research in Motion, maker of the BlackBerry, fell 7.8 percent.

The release will also have implications for AT&T, which is the sole carrier of the iPhone.

But Friday's release is just a small part of the overall iPhone picture. The real test for Apple in the long-term will be how many people shell out $500 or more for the phone and how well the company responds to that demand.

Further, any technical problems with the iPhone could hurt Apple's stock, testing investors' faith in the company.

The phone will cost $499 for four gigabytes of memory or $599 for a model with twice the memory -- that's much more costly than traditional handsets that often are knocked down to $100 or even less with contracts. The iPhone will only work on the network of AT&T, until recently Cingular Wireless, and requires a two-year service contract.

IDC Research, of Framingham, Mass., found that only 10 percent of those it surveyed would buy the iPhone at $499.

More than two of three people surveyed expressed interest but most said they were unlikely to buy based on the price and having to switch to AT&T.

It doesn't help Apple if everybody wants an iPhone, and not enough people buy one. But the company could also benefit from a possible "spillover" effect.

If consumers buy an iPhone and fall in love with it, they might be inclined to buy other Apple products, such as a Macintosh computer, that they might have not previously considered.

Apple has seen such spillover in the past with the success of its iPod music player.

"All eyes are now on the June 29 launch of the iPhone, which we continue to believe is not without risks," JP Morgan analysts wrote in a recent note to investors.

JP Morgan says the true test for Apple comes as "we move from `the buzz factor' surrounding the iPhone to true fundamentals."

The limited initial supply of the phone adds to the risk that other, similar products, could cannibalize Apple's business as happened to some extent with the iPod.

Another company to watch is Microsoft. Apple and Microsoft have long battled in the home computer world. They also went head to head with their competing portable MP3 players: the iPod and the Zune, although Apple's product has well outsold the Zune.

Microsoft hasn't announced any plans for its own phone, but the company has a major influence in the smart phone world with its own operating system. For instance, Palm's Treo can come with Palm's own operating system or Microsoft Mobile. Other smartphones have also started to use Microsoft's software.

The ultimate success or failure of iPhone will probably depend on the price of the phone itself.

"We remain concerned with the iPhone price, particularly considering the cost of the two-year contract," JP Morgan wrote. "We continue to believe that much of the stock's recent run is dependent on a nearly flawless launch of the iPhone. … we caution that the euphoria over the iPhone could ease fairly quickly, particularly given the lofty expectations for the device."