IDC said its Worldwide Quarterly Mobile Phone Tracker recorded a fourth consecutive quarter of year-on-year declines. But the company said it was of the view that growth would return by 2019, though it was not possible to predict what shape it would take.
In Q3, Samsung saw a drop of 13.4% in shipments, down to 72.2 million units. This was one of the main factors contributing to the downward trend in the quarter.
And secondly, China, the biggest market for smartphones with about a third of global shipments, also showed a fall for the sixth straight quarter.
Domestic shipments in China had shown a drop, down 11% in the first half of 2018, and continuing into the third quarter. IDC said it expected this decline to slow, with flat growth returning in 2019.
"China's domestic market continues to be challenged as overall consumer spending around smartphones has been down," said Ryan Reith, program vice-president with IDC's Worldwide Mobile Device Trackers.
"High penetration levels, mixed with some challenging economic times, has slowed the world's largest smartphone market.
"Despite this, we believe this market will begin to recover in 2019 and beyond, driven in the short term by a large, built up refresh cycle across all segments, and in the outer years of the forecast supported by 5G migration."
"The race at the top of the market continues to be a heated one as Huawei once again slipped past Apple to the second position," said Anthony Scarsella, research manager with IDC's Worldwide Quarterly Mobile Phone Tracker.
"Although Huawei may have beat out Apple in Q3, the holiday quarter could have Apple as the market leader thanks to the launch of three new bezel-less devices.
"No matter who leads in the overall market the holiday quarter should be an exciting one with a wide selection of new flagship devices available.
"With the new iPhones, Mate 20, Pixel 3, V40, Note 9, and OnePlus 6T, we can expect consumers will have a plethora of options when upgrade time approaches. The vast selection of high-priced handsets should move ASPs in a positive direction come next quarter."
Chart: courtesy IDC