Smartphone sales are expected to grow 7 percent in 2016 to 1.5 billion against 14.4 percent growth achieved in 2015, according to Gartner.

Gartner estimates that 139 million smartphones will be sold in India in 2016, growing 29.5 percent year over year.

This slow growth will be a bad news for the global smartphone majors such as Samsung, Apple, Lenovo, Huawei, among others.

In 2020, smartphone sales will reach 1.9 billion units.

Smartphone sales recorded 74 percent growth in 2010.

First, high smartphone penetration in mature markets is one of the main reasons for the slow down in the global smartphone market.

Gartner said the smartphone penetration in the mature markets of North America, Western Europe, Japan and mature Asia Pacific is 90 percent. Mobile phone users in mature markets are not replacing or upgrading their smartphone as often as in previous years.

In the mature markets, premium phone users are extending life cycles to 2.5 years, which is not going to change drastically over the next five years, said Gartner.

Second, telecom network operators have moved away from subsidies providing a free smartphone every two years, which has led to more varied upgrade cycles.

Telecoms have introduced financing programs and vendors such as Apple offer upgrade programs that provide users with new hardware after only 12 months.

In emerging markets, the average lifetime of premium phones is between 2.2 and 2.5 years, while basic phones have an average lifetime of three years and more.

Since mature markets are saturated, the focus for many vendors is on India and China. India has the highest growth potential. Sales of feature phones totaled 167 million units in 2015, 61 percent of total mobile phone sales in India.

Gartner estimates that 139 million smartphones will be sold in India in 2016, growing 29.5 percent. ASPs of mobile phones in India remain under $70, and smartphones under $120 will continue to contribute around 50 percent of overall smartphone sales in 2016.

Sales of smartphones in China were flat in 2015, after achieving 16 percent growth in 2014.

Sales of smartphones in China represented 95 percent of total mobile phone sales in 2015. Similar to India, falling ASPs for smartphones will make them more affordable for users.

At least one non-traditional phone maker will be among the top five smartphone brands in China by 2018, said Gartner.