Developer advertising platform AdDuplex has released data for the month of March. The report is based on data collected from 389 different Windows Phone apps that utilise the AdDuplex SDK (v2). March 1st was the designated date for the data to be withdrawn and analysed. So what's new in the report? Well, Windows Phone 8 is growing, but Windows Phone 7 still holds out strong and the Lumia 822 is evidently selling well.

Windows Phone 8 versus Windows Phone 7: Worldwide Windows Phone 8 Market share on AdDuplex from January through March shows an interesting trend with 19%, 26% and 31% share respectively for the new OS, demonstrating strong and seemingly consistent growth. Conversely, Windows Phone 7.x has dropped from 81% in January to just 68% this last month, meaning conversion (or people just switching) is continuing. Best VPN providers 2020: Learn about ExpressVPN, NordVPN & more

When we talk about countries and which markets are ranking above others, the USA is topping the tables on 11.3 percent with India (7.6 percent), China (7.5 percent), Mexico (7.5 percent) and Italy (7.4 percent) closely behind. While the top three remain in the same positions, their slices have been reduced with Russia, the UK, Brazil, Germany and France taking more of the pie.

AdDuplex also goes into some detail how European markets are developing with new Windows Phone 8 hardware launching at retailers and mobile operators. It's not surprising to see early Lumia hardware still among the most popular handsets as these markets witnessed some heavy Windows Phone 7 marketing. Check the following chart as an example:

It's interesting to note that the Lumia 620 is already at 4%, which is not too far from the Lumia 710 at 5% making that device's fast ascent noteworthy. Verizon has sold more Lumia 822s than AT&T's Lumia 920?

In one of the more interesting tidbits for US market share we can see how the Lumia 822 (21%) has passed the Lumia 920 (18%), which is an impressive gain by Verizon. Of course, that phone is often free on contract, and Verizon has been pushing the Lumia 822 through various TV commercials and holiday specials e.g. Valentine's Day promotion. That's still an impressive accomplishment though as the Lumia 920 clearly gets the most headlines. The Lumia 822 back in January only had about 10% of the market by comparison. Nokia still dominates in the US