GLOBAL: Global smartphones sales grew at 7% in the first quarter of 2015, significantly slower than a year earlier as demand slumped in China and Developed Asia.

New data from GfK reveal that unit demand in China was down 14% in Q1 2015 while in Developed Asia sales had fallen 5%.

Kevin Walsh, director of trends and forecasting at GfK, attributed the weakness in China to a slowdown in 3G demand, which had not been offset by 4G growth. But he expected China would return to growth in the second half of the year, "driven by a continued 4G ramp-up".

And 4G is proving to be an important factor, as 4G units now account for more than 50% of the global market; GfK predicted their share will hit 59% by the fourth quarter.

Some large markets are lagging well behind in this respect: 4G share in India stood at 4% in Q1 but is expected to grow to 7% this year, while in Indonesia it is forecast to rise from 7% to 10% over the same period.

Emerging Asian countries and the Middle East & Africa were the fastest growing regions in Q1, with unit sales of smartphones jumping 30% in each, followed by Latin America, where growth hit 22%.

And while unit sales increased in Western Europe and Central & Eastern Europe, the value of sales in both these regions declined, the former "dragged down" by Spain and France, the latter hit by the macroeconomic situation in Russia.

GfK also noted the trend to larger screens, reporting that smartphones with screens of five inches or more now constituted 47% of the global market, up from 32% a year ago.

In some markets their share was rather higher – 70% in North America, home of the iPhone 6. In China larger screens have almost doubled their share in 12 months, leaping from 32% to 57% as cheaper models have flooeded the market

For 2015 GfK forecast global smartphone unit demand to grow 10% year on year, less than half the 23% of 214. "Emerging Asia is forecast to be the fastest growing region, driven by India and Indonesia, where low smartphone penetration leaves plenty of room for growth," said Walsh.

Data sourced from GfK; additional content by Warc staff