"Twitter does not actually operate in China, due to a government ban. But it has an office in Hong Kong to focus on Chinese advertising customers and to work with developers there, too.Twitter’s China head says bye — adding another top exec departure to the heap as 2016 ends - Recode
Chen is among many top execs who have left Twitter recently, in the wake of a failed sales process and continued difficult efforts to reinvigorate its growth. Those departing of late include CTO Adam Messinger; COO Adam Bain; and product exec Josh McFarland. There was also a whole passel heading out earlier in the year."
Monday, January 02, 2017
Twitter’s China head says bye — adding another top exec departure to the heap as 2016 ends - Recode
Also see Twitter CEO Solicits Product Feedback as He Takes Larger Role (Bloomberg)