China\'s largest telecom operator, China Mobile, and Orange, a major telecom operator headquartered in France, jointly announced at the Mobile World Congress held in Barcelona that they would cooperate in developing a TD-FDD smartphone. The two companies said they would join hands in the design, research and development and sales of a 4G LTE smartphone that supports both the TD-LTE and LTE-FDD standards, the telecom news portal cctime.com reported on Wednesday.