Delete comment from: Ken Shirriff's blog
The MOV is not properly protecting the diodes at the input of the rectifier. Current spikes induced in L1 and the input choke while plugging into a live socket (bzzzt, click, zap sound) can cause diode D4 to go short, resulting in mains voltage on the metal parts of the phone case.
Apple, fix your charger before more people DIE!!!!!
Jul 25, 2013, 8:37:48 PM
Posted to Apple iPhone charger teardown: quality in a tiny expensive package