Just a week after we heard that Windows Phone 8.1 core had finished, Microsoft is ready with the final version of its platform, with copies reportedly sent to manufacturing partners for testing on old and new hardware. According to different websites, the first Windows Phone 8.1 models will be available on the market on April 23, with Lumia 630, Lumia 930 and Samsung Ativ SE being the main contenders. Other companies such as HTC, Micromax, Ucall and more are also working on new devices, which could launch in Q2/Q3 in 2014.