HONG KONG — The most important market for Chinese smartphone makers may no longer be China.

For years, hundreds of millions of Chinese have purchased new smartphones. In the process they lifted the fortunes of local handset makers, from the well known like Huawei and Lenovo to the obscure like Coolpad and Gionee.

But the era of fast growth is coming to an end in China, where the research group IDC said on Monday that phone sales fell 4 percent in the first quarter from a year earlier, the first contraction in six years. IDC expects no growth in China’s smartphone market in 2015.

The saturated Chinese market — more than 800 million people there use smartphones, according to IDC — means fewer new buyers, and a slowing economy means less spending. So Chinese companies are turning to India, trying to catch a $14.5 billion market on the way up.

“It is India first for us,” said Varun Sharma, Coolpad’s chief executive of Indian operations. He said Coolpad, a Shenzhen-based company, planned to use its patents and manufacturing infrastructure to sell devices “at $100 price points for the Indian market and not at $800 or $1,000 price points that global brands are doing.”