Downgrade Windows 10 mobile to 8.1

[Jakeem Votacion]

A friend have a Nokia Lumia 930 and is planning to sell it. Now I'm interested in buying it (for nostalgia's sake) but unfortunately not a fan of Windows 10 Mobile. Is downgrade possible from Windows 10 to Windows Phone 8.1? And is Facebook, Messenger and Instagram still available for Windows Phone 8.1?

 

[T Moore]

Yes, the WDRT will take the phone back to 8.1.
No, Facebook and messenger are not available for 8.1
WDRT
https://support.microsoft.com/en-us/help/12379/windows-10-mobile-device-recovery-tool-faq