It has been quite some time, Windows Phone 8.1 was over. Now the Windows 10 Phone is gradually declining and will die just as Windows Phone 8.1.
As per the vice president of Microsoft the company will continue supporting the mobile OS with the bug fixes but new features and hardware will not be introduced anymore.
The reason is that developers have never been interested in this platform. The company was not able to find any partners as well. In addition, Windows 10 Mobile users have also not been many.
That is why rather than investing additional on a new Windows OS invention, Microsoft will be looking for other alternatives with regard to improving the links between phone and PC.