This handout picture, released by Apple and taken in March, shows Apple chief executive Tim Cook (L) visiting the iPhone production line at Foxconn manufacturing facility in Zhengzhou, China's ... more 

This handout picture, released by Apple and taken in March, shows Apple chief executive Tim Cook (L) visiting the iPhone production line at Foxconn manufacturing facility in Zhengzhou, China's north-central Henan province. Thousands of workers have gone on strike at the plant, a labour rights group said on Saturday less