Wang Kai shows the debris of his iPhone 4, Apple's 4th-generation smartphone, after it ignited in Chongqing, on July 9, 2013. He said he was sound asleep when the phone spontaneously combusted and burnt his mat. Apple's after-sales service has been notified, saying they are investigating whether user error is to blame. [Photo by Yu Xiao/Asianewsphoto]