AdDuplex is back, this time with a look at Windows Phone device usage share for August 2014. This month, there are no major changes, but popular new devices like the Lumia 930 and Lumia 630 are moving up in the ranks. And here in the US, low-end devices rule, and we have a wide range of choice between wireless carriers.

As you may remember, AdDuplex bills itself as the largest cross-promotion network for Windows Phone and Windows 8 apps, empowering developers and publishers to promote their apps for free by helping each other. And each month it provides a tantalizing glimpse at which Windows Phone (and Windows) devices people are actually using.

Here's what's happening this month.

Lumia 630 breaks into the top ten. After just a few months in the market, the Lumia 630—which is the dual-SIM, international version of the Lumia 635 I love so much—has broken into the worldwide top ten, and finally bumped the years-old 820 out of there. The Lumia 630 is now the world's 8th most-used Windows Phone handset.

Lumia 930 moves up too. It's not in the top 10, but the flagship Lumia 930 has made a nice jump worldwide, too, moving from #31 last month to #28. This is semi-notable because Nokia's high-end Windows Phones hasn't historically performed very well. (And not at all since the Lumia 920, which is years-old.)

Nokia hits 95 percent of usage. Well, it finally happened, though one has to wonder whether this is the peak given all the new hardware partners coming to market: Exactly 95 percent of all Windows Phone handsets in use in August were Nokia devices. HTC was a distant number two with 3.3 percent, and Samsung came in at 1.1 percent.

Windows Phone 8.1 hits 24.4 percent of all Windows Phone handsets. And that's pretty incredible given the relatively slow rate at which Windows Phone 8.1 is being rolled out by wireless carriers. That's well ahead of Windows Phone 7.x (19.2 percent) and well below Windows Phone 8.0 (56.5 percent).

The migration from Windows Phone 7.x to 8.x. In an attempt to understand how Windows Phone 7.x is declining, AdDuplex looked at new Windows Phone 7.x app development and sees a fairly linear move downward throughout 2014. If this trend continues, developers will essentially abandon new app development on Windows Phone 7.x, to focus on 8.x apps instead, by the end of 2014. This makes sense: Windows Phone 8 arrived fully two years ago, after all.

United States dominated by low-end devices. With the Lumia 630 moving into the 4th position overall in the United States, the only phones we see in the top ten that were released in the past year are low-end devices: The Lumia 521 (27.5 percent, still number one), the Lumia 520 (16.4 percent) and the 630 (5.2 percent). I'm curious that the 635 isn't in there yet, but I bet it will be soon. By comparison, the recently-released HTC One—a high-end flagship device—debuts at number 40 in the US.

US wireless carriers see wide coverage. We're seeing an interesting spread of wireless carrier activity in the US, with AT&T in the number one position with 33.6 percent of usage, followed by T-Mobile (22.2 percent), Verizon (15 percent), Cricket (10.9 percent) and MetroPCS (9.3 percent). Seems like Windows Phone fans have a lot of choice all of a sudden.

New devices. As you must know, Microsoft/Nokia have new devices planned for September, and models like the Lumia 830 and 730 are rumored for this week's IFA. Not surprisingly, then, AdDuplex has seen a number of coming Windows Phone handsets appear in the usage statistics, including the Nokia RM-1090/1091 (with an odd screen resolution of 960 x 540), the HTC 0P6B180 (the AT&T and T-Mobile versions of the HTC One M8 for Windows), and the BLU w5101, which is a 720p device that's popping up in China and the United States.

Good stuff as always. You can learn more—including usage for a number of other countries—in the AdDuplex Windows Phone Device Statistics for August 2014 report on the web.

Note: AdDuplex measures the usage of individual Windows Phone handset models only. It does not measure the usage of Windows Phone vs. competing mobile platforms such as Android or iOS.