It’s not the first report of iPhone batteries overheating, though the incidents appear to be rare and have also affected other cellphones. In 2011, an iPhone 4 turned red hot and began emitting dense smoke in the cabin of a commercial flight in Australia; no one was injured. Last year, Samsung said it would investigate a report of its Galaxy S III bursting into flames in Ireland. And also last year, a Motorola Droid Bionic was said to have caught fire in its owner’s pants.
In Bhujle’s case, her iPhone 4S was sitting on her coffee table on Monday, Jan. 28, when the phone’s display unexpectedly turned on and then off. “Within a minute, there was a very strong smell—it smelled like something was burning,” she told Quartz in an interview today. “I picked up my phone and it was very, very hot. It wouldn’t turn on. In the following minute. I couldn’t hold it because it was too hot to touch. I was panicking. I expected it to explode or something.”
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IMO I think it's a coincidence it started 'oozing a dark liquid' on a coffee table, where the 'liquid' just so happens to look like coffee.