Yesterday , 17 March 2016 00:22 GMT+8 , approx. 09.22 am in the Redmond,WA, US, – Microsoft has released the Windows 10 Mobile Update to all selected older WP 8.1 devices.

The Phones and Devices that can upgrade to Windows 10 is :

Lumia 1520, 930, 640, 640XL, 730, 735, 830, 532, 535, 540, 635 1GB, 636 1GB, 638 1GB, 430, 435
BLU Win HD w510u, BLU Win HD LTE x150q,
MCJ Madosma Q501

How to Upgrade?

The Upgrade process is quite easy at first. You just need to Download an app called the Windows 10 Upgrade Advisor :