As of April 2019, my main computer is a home-built Windows PC in an older Dell minitower case. Windows 10 Pro 64-bit edition and I jumped in early but stay current, now on the November 2019 Update.
I upgraded the RAM with an additional 8 GB and am still on the lookout for a used Core i7 CPU to help content load faster. The i3 still runs decently.
Intel Core i3 CPU
16 GB of DDR3 RAM
Windows 10 & programs are installed
on a Samsung 850 Pro SSD
(2) 1 TB Western Digital HDDs
MSI 1 GB GDDR5 graphics card
500 W Antec PSU
APC 650 UPS
Samsung HD 22" monitor
Logitech K800 wireless, backlit keyboard
and M510 mouse
I back up my data to an external HDD and disconnect it after backing up.
For mobile computing, I rely on a rebuilt Dell Ultrabook, the Latitude E7240. I dream about moving to a Surface Pro or other 2-in-1 laptop, but I'm happy with this and really do like a solid keyboard while mobile.
My smartphone at present is the Google Pixel 2.
I have an original iPad & a Mini 2. Both still work fine but I can't add most any app or even update old apps.
I now have an older MacBook Pro, with iffy WiFi that fails from time to time, but the Ethernet port works fine. I do work on Macs now, as well. I currently have an old iMac all-in-one hanging around and occasionally use it for YouTube entertainment.