Worldwide smartphone sales in the second quarter of 2015 grew at their slowest rate in two years, up 13.5% to 330 million units. For the first time, smartphone sales in China declined — by 4% — year over year. Worldwide sales rose to 329.68 million units in the quarter, up from 290.38 million units a year ago.

Samsung Electronics held onto the market share lead in the quarter with sales to end users totaling over 72 million units to nab 21.9% of the global market. Apple Inc. (NASDAQ: AAPL) ranked second with sales of more than 48 million units for a 14.6% share. In the second quarter of 2014, Samsung claimed 26.2% of the market with unit sales of more than 76 million and Apple posted unit sales of more than 35 million units for a 12.2% share.

Adding in sales of feature phones, total worldwide sales of mobile phones reached 445.76 million in the second quarter, compared with 444.19 million in the same period last year. The data were reported by Gartner on Thursday.

Among other smartphone makers, Huawei posted a second-quarter share of 7.8% on unit sales of 25.83 million units, up more than 8 million units year over year and the largest share gain of any maker, rising from a 6.1% share a year ago. Lenovo (including Motorola) lost share year over year with unit sales of 16.41 million (5% share), and Xiaomi pulled nearly even with unit sales of 16.06 million units (5.9% share).

Gartner research director Anshul Gupta said:

While demand for lower-cost 3G and 4G smartphones continued to drive growth in emerging markets, overall smartphone sales remained mixed region by region in the second quarter of 2015. … China has reached saturation — its phone market is essentially driven by replacement, with fewer first-time buyers. Beyond the lower-end phone segment, the appeal of premium smartphones will be key for vendors to attract upgrades and to maintain or grow their market share in China.

By operating system, Android from Google Inc. (NASDAQ: GOOGL) held an 82.2% share of the market for the second quarter, down from 83.8% a year ago. Apple’s iOS share grew to 14.6% from 12.2% last year. Market share for Windows Phone from Microsoft Corp. (NASDAQ: MSFT) slipped from 2.8% a year ago to 2.5%, and BlackBerry Ltd.’s (NASDAQ: BBRY) share dropped from 0.7% to 0.4%.

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