A small but vocal minority of iPhone 3GS owners are complaining of handsets overheating, so severely in some instances that the case has been discoloured.
One reviewer for a US tech website claims the phone literally became too hot too handle. "I was using a game, and then later the web browser for reading the news about Michael Jackson, all over a Wi-Fi connection while plugged in. And in those circumstances, well... toasty doesn't even describe how surprisingly hot it got," says Melissa Perenson, reviewing the 3GS for the US edition of PC World. "It was too hot to even put the phone against my face."
Despite the heating issues, Perenson noticed no marking of her handset. Other users have reportedly not been so lucky.
The discolouration problem has only affected white handsets so far, presumably because it's more susceptible to discolouration than the black version.
"I bought a 3GS the day it came out and put on an Invisishield [popular iPhone case] as soon as I got it, and by yesterday, I looked at the back of the phone and under this Invisishield, there are brown streaks and spots all over," says Andrew on the iLounge website.
Another user on French website Nowhere Else has reported the same problem, without using any case, and posted a collection of images showing brown streaks on his handset.
The most likely cause for the overheating issue is faulty battery cells. Aaron Vronko of Rapid Repair, a company that fixes Apple handsets, told Wired magazine that the issue could prompt recalls.
"My guess is there's going to be a whole lot of batteries affected because these are from very large production runs," he said. "If you have a problem in the design of a series of batteries, it's probably going to be spread to tens of thousands, if not hundreds of thousands, and maybe more."
Apple was unavailable for comment at the time of writing!
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