The analysis was made over 20 million unique active iPhones since the devices were launched on Friday, September 20.
The research found that the country with the most iPhone 5s units sold was China, and not the U.S. or Japan as expected.
The explanation for this could be related to the introduction of the new gold option that is available for the iPhone 5s, not for 5c, which is particularly attractive to Asian markets.
Approximately 78% of the devices sold by Apple worldwide were iPhone 5s units.
China is followed by Australia, Germany, Japan, Canada and the U.S. in the list of countries where the 5s recorded a high ratio as compared to the 5c.
China sold 91% of the 5s models globally, the U.S. came in at 76% and an average of 82% was recorded in other countries.