33% of users are still running last year's iOS 10, with a further 8% using even older versions of the software.
"And, as Windows continued to drop in share, Android was able to gain 4.3 percentage points in the big five European markets, 8.2% in the U.S., and 7.5% in Japan".
iOS 11 has been installed on just 59% of compatible iPhones and iPads, with owners seeming reticent to install the latest version of Apple's mobile operating system.
Kantar believes that this drop in sales of the iPhone was inevitable as customers would eventually be upgrading to the iPhone X.
Apple launched the iPhone X in the beginning of November, instead of in September when it launched the iPhone 8 and iPhone 8 Plus. "Considering the complete overhaul that the iPhone X offers, consumers may be postponing their purchase decisions until they can test the iPhone X and decide whether the higher price, compared to the iPhone 8, is worth the premium to them". However, giants like Huawei, Xiaomi, OPPO, and Vivo must be feeling the tension as Apple has obtained a small, but noticeable 0.5 percent market share jump in China to 17.4 percent. Apple was one of the top five brands that now makes up 91% of all sales in the country, up from 79% in the prior year. Samsung's performance in China continues to deteriorate, with its share now down to just 2.2% of that market.