The listing on Zauba points towards a 5.7-inch phone in the making. However it does not mention a platform nor does it mention any brand. However it has been speculated that the device could be a Windows Phone handset as the country that the device was shipped from is Finland which is where Nokia operates from.
It has also been mentioned that previously Microsoft’s listings on Zauba also lacked any identification which is why some have speculated that this particular listing could indeed be for a Windows Phone device. It is unclear if we are looking at a high-end smartphone here, possibly of the flagship variety, or if we could be looking at a mid-ranger with a large display as one of its selling points.
Now we know that Microsoft has promised us a flagship Windows Phone handset although previous rumors have suggested a late 2015 release, possibly after the release of Windows 10 Mobile.