According to the latest smartphone sales data from Kantar Worldpanel ComTech, the new Apple iPhone 5 has significantly slowed the momentum of Android.

The slowdown has been observed in both U.S. and U.K. markets. The market research firm finds that Android’s rate of growth slowed just as iPhone 5 sales began to take off.

“Apple has increased its share from 18.1% to 28.0% in the past year across Britain, while in the US its share increased by 14.2 percentage points,” the new research reveals.

    And in the race for smartphone supremacy, Great Britain is a huge market for mobile sales. In Great Britain alone, smartphones made up 81% of all mobile sales, with this figure rising to 94% among 25-34 year olds.

“While this latest data set only includes one week of iPhone 5 sales, we can see that in markets with a large number of existing Apple customers, sales have already seen a significant boost,” says Dominic Sunnebo, global consumer insight director at Kantar Worldpanel ComTech. “We expect this momentum to be fully realized in the next set of results.”

“The rollout of 4G across the UK tomorrow is great news for consumers wishing to replicate their home WiFi experience on the go,” Sunnebo adds. “EE is in the unique position of being the only operator currently able to offer 4G services in the UK, but how much of an impact this will have on the competitive landscape remains an unknown.”