Apple Inc.'s latest iPhones might not be performing as strong as expected based on market share figures in major markets.

According to Kantar Worldpanel, sales of the iPhone 5c and iPhone 5s have been strong on a month-to-month basis since its release in September. However, the strong sales were not echoed in shares of major markets.

"While there's no doubt that sales of the iPhone 5S and 5C have been strong, resurgent performances from LG, Sony and Nokia have made making year on year share gains increasingly challenging for Apple," said Kantar Worldpanel's Strategic Insight Director Dominic Sunnebo. "Windows Phone, for example, is now the third largest [operating system] across Europe with 10.0 [percent] - more than double its share compared with last year."

Kantar Worldpanel noted the strong sales of the iPhone 5c and iPhone 5s may be a result of "high levels of customer satisfaction" despite concerns the iPhone 5c would "damage" Apple's appeal.

"Some people worried that Apple was risking its historically high consumer satisfaction levels by releasing a lower cost, plastic iPhone," Sunnebo added.  "However, the latest data for the U.S. shows that the iPhone 5C has an average owner recommendation score of 9.0/10 versus 9.1/10 for the iPhone 5S.  Both devices attract different customers but crucially each group of owners remains very happy with their choice and are recommending it to others."

As BGR noted, the September to November 2012 period led Apple's U.S. market share to grow from 34.6 percent to 53.3 percent. In the same period in 2013, Apple's market share grew from 35.9 percent to 43.1 percent.

As Latino Post reported, Apple's iOS platform lost its first place rank as the top smartphone operating system in the U.S. during the three months ending in November 2013. While iOS accounted for 43.1 percent of the market share, Google's Android platform increased by 8 percentage points and finished November with 50.3 percent. Windows Phone placed third with 4.7 percent due to an increase of 2.1 percentage points in comparison to the three months ending in November 2012.

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