This is a very minor thing, but I noticed that after I changed the name of my device to 'My Kindle', the word 'kindle' in the top left of the device was no longer orange. I changed it to 'my kindle' and it's orange again. Not important, but it's a little aesthetic thing that adds a nice touch.
So the word 'kindle' needs to be in lowercase.
To change your device name, go to the Amazon web site and then find the link to Manager Your Kindle:
https://www.amazon.com/gp/digital/fi...#manageDevices