BEIJING (BLOOMBERG) - Xiaomi, the once-hot Chinese smartphone maker, saw shipments tumble 38 per cent in China in the second quarter as Huawei Technologies took over the top spot in the world's largest market, according to research from International Data Corp.

Xiaomi shipped 10.5 million smartphones in the quarter, down from 17.1 million in the same period a year earlier. That made the company the fourth-largest competitor in the market behind Huawei, OPPO and Vivo, according to IDC.

Xiaomi disputed the IDC numbers, citing data released by other researchers. It said IHS showed shipments of 14.2 million units while Strategy Analytics has the company at 12.8 million units, the Beijing-based company said in a statement.

The Chinese market, the world's biggest, has grown increasingly competitive as domestic manufacturers have improved their quality, design and marketing, putting pressure on global leaders Apple and Samsung Electronics. Apple saw shipments in China drop 32 per cent in the second quarter and the iPhone maker fell to fifth in the market, according to IDC.

The research firm said that Huawei and OPPO gained ground by concentrating on one or two key attributes in their marketing messages. Huawei emphasized the Leica lens now available on its phones, while OPPO pitched fast-charging technology.

Apple's global shipments are set to decline in 2016 as it continues to lose ground in its largest overseas market, Canalys said in a separate report.

"The iPhones lack features such as waterproofing and wireless charging. Apple needs to catch up with the competition if it wants to compete," Canalys research analyst Jessie Ding wrote.