Worldwide sales of smartphones to end users are on track to reach 1.57 billion units in 2020, an increase of 3% year-over-year, according to Gartner.

The company states that in 2019, worldwide smartphone sales declined 2%, the first time since 2008 that the global smartphone market experienced a decline.

Gartner added from a regional perspective, the Middle East and North Africa, mature Asia/Pacific and Greater China (China, Taiwan and Hong Kong) regions will exhibit the highest growth rates in 2020, at 5.9%, 5.7% and 5.1%, respectively.

"2019 was a challenging year for smartphone vendors, primarily due to oversupply in the high-end sector in mature markets and longer replacement cycles overall," said Annette Zimmermann, research vice president at Gartner.

In late November 2019 Gartner said the market in the third quarter of that year contracted by 0.4% year-on-year.

Zimmermann continued, "However, in 2020, the market is expected to rebound with the introduction of 5G network coverage in more countries and as users, who may have delayed their smartphone purchases until 2020 in expectation of price reductions, begin buying again."

Gartner forecasts that sales of 5G mobile phones will total 221 million units in 2020 - which will account for 12% of overall mobile phone sales - and more than double in 2021, to 489 million units.

"The commercialisation of 5G phones will accelerate in 2020. 5G phones costing under $300 have been announced, so sales growth of 5G phones is expected to exceed that of 4G phones over twelve months," said Zimmermann.

The research firm added that strong demand for 5G phones in general, together with expectations of Apple's first 5G iPhone, will bolster demand for smartphones, particularly in Asia/Pacific and Greater China.

In terms of smartphone sales, Greater China and emerging Asia/Pacific will maintain their No. 1 and No. 2 positions globally in 2020, with respective sales of 432.3 million and 376.8 million smartphones