The figures, from Flurry Analytics, are double those reported during the same period in 2010.
Flurry Analytics also said that more than 242 million apps were downloaded via the App Store and the Android Market on December 25. Industry experts are attributing the surge to the wider availability of budget smartphones.
Google's Andy Rubin announced via Twitter that more than 3.7m Android smartphones were sold over the Christmas weekend. Earlier this month, the senior vice president of mobile revealed that 700,000 Android devices were activated each day.
Elsewhere, web analytics firm IBM Coremetrics reported that online shopping on Christmas Day rose by 16% compared to 2010. Apple's iPad was the most widely-used mobile device, hosting 7% of all web transactions.
Pre-Christmas sales figures from across Europe suggested that Android handsets are significantly outselling their iOS counterparts in Eurozone territories. However, Apple reported increased marketshare in Britain, the US and Australia.
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