Although Samsung Electronics and Apple continue to dominate the high-end of the smartphone market, smartphones are by in large marketed by firms based in China.

According to a report by market research firm IC Insights, nine of the top 12 smartphone vendors call China home. Only one other vendor from outside China - LG Electronics - is among the leading suppliers worldwide.

IC Insights says that Samsung and Apple dominated the smartphone market from 2015 through 2017. In total, these two companies shipped 526 million smartphones and held a combined 35% share of the total smartphone market in 2016. Moreover, these two companies shipped over one-half billion smartphones (533 million) in 2017 with their combined smartphone unit marketshare increasing one point to 36%.

Samsung's total smartphone unit sales were up by 2% in 2017 to 317 million units, slightly outpacing the total smartphone market that grew by 1%. Meanwhile, orders for new Apple iPhones fell 7% in 2016, much worse than the 4% growth rate exhibited for the worldwide smartphone market. However, Apple rebounded somewhat in 2017 with its total smartphone unit shipments being flat last year.

It appears that the up-and-coming Chinese producers like Huawei, OPPO, Vivo, and Xiaomi are giving a serious challenge to Samsung and Apple for smartphone marketshare. However, Samsung and Apple still hold a commanding share of the high-end smartphone segment - that is, smartphones priced more than $200.

The number four and five ranked smartphone suppliers on the list are owned by the same China-based parent company - BBK Electronics. Combined handset unit shipments from these two companies were 213.1 million in 2017, just 2.7 million less than second-ranked Apple.

Overall, there was very little middle ground with regard to smartphone shipment growth rates among the top 12 suppliers in 2017. Four of the top 12 companies registered double-digit unit growth while the other eight companies logged 2% or less increases and four of those displayed a double-digit decline. Three Chinese smartphone suppliers (Xiaomi, OPPO, and Vivo) saw their shipments surge at least 24% in 2017. Xiaomi displayed the highest growth rate of any of the top-12 smartphone suppliers (73%). Meanwhile, another three Chinese suppliers (LeEco/Coolpad, ZTE, and TCL) saw their smartphone shipments fall by more than 20% last year.

Combined, the nine leading smartphone suppliers based in China shipped 626 million smartphones in 2017, an 11% increase from 565 million smartphones that these nine companies shipped in 2016. The top nine Chinese smartphone suppliers together held a 42% share of the worldwide smartphone market in 2017, up four points from the 38% share these companies held in 2016 and eight points better than the 34% combined share these companies held in 2015.

IC Insights projects smartphone shipments in 2018 will rise 2%, to 1.53 billion units. Moreover, smartphone unit shipments are forecast to grow at low single-digit annual rates through 2021.