After a long time of waiting, Microsoft has finally started to roll out the Windows 10 Mobile for the old devices with Windows Phone 8.1.
The Windows 10 Mobile is the more thriving platform for Windows users than the Windows Phone 8.1. The upgrade comes with more likely integration in Skype and the improvement in handling with Outlook and office apps, and much better user interference.
However, the devices that are currently running the Windows 10 Mobile insider program with Windows 10 Mobile OTA cannot install the windows official update.
Unlike the previous updates to install the upgrade, you need to start the update manually. Microsoft made an UpgradeAdvisor app to help you notify about the update availability. You can download UpgradeAdvisor from Windows Store to check if the upgrade is available for your Windows device.
According to Microsoft, following are the Devices that can be upgraded to Windows 10 Mobile; Lumia 430, Lumia 435, Lumia 532, Lumia 535, Lumia 540, Lumia 640, Lumia 640XL, Lumia 635 (1GB), Lumia 636 (1GB), Lumia 730, Lumia 735, Lumia 930, Lumia 830, Lumia 1520, BLU Win HD LTE x 150q, BLU Win HD w510u, and MCJ Madosma Q501.