Grey dot on iPad - solution

In my search within the Apple Community about seeing a grey dot on my iPad screen, I saw that the solution I found was not written anywhere. So, just in case this is an issue for anyone else, here's what I discovered.

My new iPad Air is attached to a Logitech Bluetooth keyboard. After trying all sorts of adjustments (within Settings) to get the grey dot to disappear, I discovered that the dot is the pointer for the track pad on the Logitech keyboard. It moves when I move my finger on the track pad. To get the dot to go away, I removed the iPad from the Logitech device, then reattached it. Voila - no dot.

I'm not sure why the dot appeared as suddenly as it did (I've had the new iPad for 2 months with no issues), and I don't know whether this is a Logitech issue or an Apple issue, but at least the dot is gone.