Global smartphone shipments are expected to grow 10.4% on year, instead of a previous forecast of an 11.3% growth, to 1.44 billion units in 2015, according to the latest data released by IDC.

However, steadily falling ASPs will fuel growth through the end of the forecast period, with global shipments reaching 1.9 billion units in 2019.

Smartphone shipments to China are forecast to grow just 1.2% on year in 2015 compared to a growth of 19.7% in 2014. While China will remain the largest market for smartphones throughout the forecast period, its share of the overall market is expected to drop to 23.1% in 2019, IDC said.

Android shipments globally are expected to grow from 1.06 billion units in 2014 to 1.54 billion in 2019, while iOS shipments will grow from 192.7 million in 2014 to 269.6 million in 2019.

IDC's view that Microsoft/Windows Phone will remain a marginal challenger at best has not changed.