Scale App- what is Root note "Key" setting?

Hi all,
I am delving yet further into the “Scale App” within the Midipal.
I have just found right at the end of the “Root note” page , if you scroll through C,C#.D……etc eventually you reach the mysterious “Key” setting.
Can you tell me what this is as I don’t see it on the manual page.
It seems, from a “try it and see” test, that the midipal is trying to predict what key I am in as I play, but I am not sure how this is fully realised of what I could do better to use it in a knowing way.
Please help

The lowest key played on the keyboard defines the root.

So if I am playing in Ionian with rott set to Key,

If I play with a C1 bass note I am in C Ionian , but when I change that to my second chord (say with an F1 bass note) the key will now be in F Ionian?
Whats the practical use you had in mind on this? Not being facecious by the way, I am just interested in the possibilities you saw this as opening up, perhaps Im just not being creative enough?

I was kind of hoping that Key mode would let you press down the midipal knob to put it into “select” mode, then press a keyboard note then release to select…this would have been a great way to use this as I could “click select” to switch between keys at a gig without having to scroll.

Just my 2p’s worth…

Cheers for the reply.

Someone asked for it. Wasn’t it you?

Haha, that’s probably one of the only requests you’ve had that’s NOT from me (sorry again to be the one bombarding you no, this was already in place when I assembled mine back in December, I’ve not dared to re-flash yet (although I might now that the tempura app is out.)
I will have a play with it and see if I can find a musical use.