That was almost three times the number of new device activations for second-placed Samsung (17.7%), according to Flurry, the Yahoo-owned analytics firm which examined data from more than 600,000 apps that it tracks each Christmas.
Microsoft (Nokia) took third position with 5.8% of global activations, mostly for its Lumia devices, while Sony and LG secured 1.6% and 1.4% respectively.
Fast-growing Asian brands Xiaomi, Huawei and HTC all had less than one percent market share, but Flurry emphasised that Christmas is not the most important gift-giving day of the year for most countries in Asia.
Flurry reached its findings by monitoring the key apps that users downloaded as soon as their new devices were activated and it discovered that, in the US, the number of apps installed on Christmas Day was 2.5 times higher than in the first three weeks of December.
"This is a remarkable number considering the maturity of the US market and the difficulty of getting recognised in crowded app stores," the report said.
The study also confirmed the growing popularity of larger-screen phablet devices, such as Apple's iPhone 6 Plus, with the category seeing an overall increase to 13% of all activations, up from 4% in 2013.
Meanwhile, the percentage of new activations of full-size tablets fell from 17% of all devices in 2013 to 13% this Christmas, while medium-sized phones declined one percent to 64%.
However, while the report confirmed Apple's dominance in the global device market, a separate study found US consumers prefer Samsung for customer satisfaction.
According to the latest American Customer Satisfaction Index, an annual survey of 70,000 US consumers, Samsung achieved a satisfaction rating of 81 points (out of 100), a rise of five points since last year.
This took it ahead of Apple in the opinion of US consumers, who awarded the company a satisfaction rating of 79 points, a modest two-point fall since 2013.
Data sourced from Flurry, Digital Trends; additional content by Warc staff