Last week, Microsoft made the Windows Phone 8.1 operating system available for download for all those enrolled in the company’s app development program, and some statistics on the platform’s adoption are now available.

According to data coming from AdDuplex, the new Windows Phone 8.1 operating system is now accounting for 3.1 percent of all WP devices out there.

Considering the fact that it was released as a Developer Preview iteration, which means that it still packs a series of bugs inside, the adoption rate seems quite impressive.

What’s more important, however, is the fact that well over one million devices are already running under the new platform, only one week after its release.

As WPCentral explains, the total number of Windows Phone handsets out there was estimated to be of around 50 million units back in January, despite the fact that no official confirmation on the matter has been provided as of now.

Basically, this means that Windows Phone 8.1 is currently loaded on over 1.5 million handsets, provided that the estimate is accurate.

AdDuplex also shows that Windows Phone 8 is currently enjoying 78 percent market share in the WP segment, and that Windows Phone 7 is down to only 18.9 percent.

When it comes to manufacturers, Nokia continues to enjoy the largest market share on Windows Phone, at 93.5 percent. HTC comes in second, at only 4.4 percent, with Samsung placed third, at 1.3 percent, and Huawei fourth, at 0.8 percent.

Soon, however, these figures might change, due to the fact that more mobile phone makers out there are set to launch Windows Phone handsets.

Nokia leads the Windows Phone market

Most of these companies are expected to release entry-level, cheap Windows Phone handsets, which will compete with phones such as Lumia 520, currently the most popular device in the series, at 34.4 percent market share.

The high-end Lumia 920 is only the second most popular Windows Phone device out there, at 6.4 percent market share, with the mid-level Lumia 625 coming in on the third position, at 6.3 percent.

AdDuplex also unveils that AT&T is currently selling the most Windows Phone handsets in the US, with 34 percent market share, with T-Mobile and MetroPCS trailing it at 23.8 percent and 15.1 percent, respectively. Verizon is placed fourth, with 13.7 percent market share.