I used windows phones for four years, with a 1020 and a 640XL, and a 535 used by my wife.
I recently changed to an Android phone running the 8.1 version. I wouldn't go back, but Android is good - not great.
I still wanted to use Outlook for mail calendar and contacts, and OneDrive for photo backup and cloud storage. Google has made that difficult and defaults to Gmail, G drive and G Photos. It took a lot of digging to find settings to make Outlook.com my primary
mail client, and to synchronise contacts. However, perhaps as i have over 2000 contacts, the windows phone wasn't synchronising contacts with my desktop anyway.
I had reached the point where the slowness, glitches, breakdowns, and limited apps of the windows phones just made their Microsoft system and applications compatibility advantages pointless.
Microsoft has developed a lot of apps for the Android platform, including office software and a shell for the OS. It looks to me as though Microsoft has now decided to put its money into developing solutions for the Android platform.
So seriously, there should be a Microsoft site thread to assist windows phone users changing to Android.