Windows 10 Mobile was the best of them all at it's height
Loved it. It was a fantastic slick mobile OS.
I HATED going back to Android after support started dropping from it
Back on Android (Moto X4) myself after a few years on the 640. Have to say I'm loving it so far. Still getting used to it but my hardware choice was an upgrade and I have a few apps I can use for work now that I didn't have with Win10 Mobile.