The company has said an update to its operating system – iOS 4.0.1 – “improves the formula to determine how many bars of signal strength to display”.
Many users have reported problems with reception on their device, which is caused when their left-hand covers an antenna in the lower left-hand corner of the iPhone 4. This so-called “death grip” issue will not be corrected by the software update.
The company started contacting US-based technology journalists on Wednesday, inviting them to the hastily convened press conference.
Apple has given no further clues about the nature of the event, but has confirmed that the key topic for discussion will be iPhone 4.
The company has faced a barrage of criticism in recent weeks for the way in which it has handled a series of problems with its flagship device. Many users have reported a loss of reception whenever the hold the phone in their left hand, covering one of the antenna built in to the stainless steel band that runs around the middle of the device.
Apple said that such problems were common to all mobile phones, while Steve Jobs, Apple’s chief executive, responded to one angry customer’s email by telling him to simply stop holding his iPhone like that.
Apple issued a statement earlier this month claiming the reception issues were a result of an error in the way the iPhone calculated signal strength, usually indicated by a set of bars in the corner of the screen.
“Our formula, in many instances, mistakenly displays two more bars than it should for a given signal strength,” Apple said.
However, many users have rejected the diagnosis, claiming that holding the phone in a certain way actually reduces the signal strength, rather than simply the way the phone interprets the level of reception.
Earlier this week, a leading analyst warned that a recall of iPhone 4s would cost Apple around $1.5 billion. Apple sold more than 1.7 million iPhone 4s in its first three days on sale.
Toni Sacconaghi, an analyst with Bernstein Research, said such a recall was “highly unlikely”, and that Apple would be more likely to give away cases to customers affected by the issue.
Consumer Reports, a US consumer watchdog, also issued a damning review of the iPhone 4, highlighting the signal problems, and concluding that it “could not recommend” the device as a result. It also urged Apple to fix the issue quickly, at no additional cost to customers.
The emergency press conference is almost unheard of for Apple, which prides itself on the carefully timed release of information, and has dealt with other problems in the past simply by issuing an open letter from Jobs.
However, the company has come in for strong criticism for the way it has handled these signal problems, with many branding its attitude towards loyal customers as “arrogant”.
“I think the fact they’ve called this press conference at such short notice is indicative of the seriousness of the situation, and the way in which it’s snowballed,” said Geoff Blaber, an analyst with CCS Insight.
“Apple needs to be seen to be taking some steps to address this problem. I think a full product recall is highly unlikely, but there is a clear need to be proactive.
“There’s less than a week to go before Apple’s next quarterly earnings call, so the timing of this press conference is crucial.”
Blaber said that Apple may give away cases to iPhone 4 users, but that by doing so, the company would be making a tacit admission that there was a significant hardware problem.
Sacconaghi estimated that it would cost Apple around $1 per unit to give away cases to iPhone 4 customers.