23-year-old Ma Ailun, who was allegedly electrocuted while answering a call on her iPhone, may have been using a third-party USB charger, and not the OEM model provided by Apple.
The Chinese woman's unfortunate death – which occurred while answering a call on her iPhone 4 – may be the result of a faulty AC adapter according to phone expert Xiang Ligang who was interviewed (Google translation) in the matter earlier this week. Ligang thinks that the charger may have had fewer safety measures built into its hardware, and experienced a failure.
The charger in question can be seen in the screen grab from the CCTV interview above, "traces of burning" can also be seen on the side of the iPhone 4. According to the Google translation "the phone's data cable, charger and plug wire boards are intact, the phone starts up normally."
Telecommunications expert Xiang Ligang, interviewed for the news piece, said that the "Cottage charger may cut corners, the quality of the capacitor, the protection circuit is not good, leading to the breakdown of a capacitor charger, 220V AC directly into the cell phone battery inside."
Below is a picture of the OEM Apple World Travel Adapter Kit. You can see the Apple adapter in the lower left corner of the box and how it's different from the one above that's believed to have electrocuted the woman.