I really wish this was the One True Way, but unfortunately I couldn't get this working. Installed fine but then, nothing.

On windows I had to explicitly allow the executable in the windows firewall. I didn't get any popups or warnings that it got blocked. After that, it worked fine

On Linux I also needed to adapt the firewall rules to allow it.

That's the #1 solution for devices under my control. For the rare cases, where I need to transfer personal data to/from corporate devices, I just use https://webwormhole.io/

I recently started using KDE Connect because I was fed up with the way I had to send photos from my Android phone to my Ubuntu desktop. I usually did that by email, or in some rare cases I plugged a USB cable in to connect.

KDE works over Bluetooth, I guess, but it was super fast for transferring around 20 to 30 photos at the same (maybe more might also work, didn't try that).

But the most important thing was that I could look at the thumbnails of the photos before marking them for transfer. This process was always very slow with an USB connection, because it was always trying to 'thumbnailize' every photo in the folder (which were 100s or 1000s). Picking the right photos by obscure datetime-name is not fun.