After a short time to install 5.9.2 of Qt and then without my fingers crossed even, I loaded up Qt and loaded one of the 3D Android compatible examples.
After the first build complaining about API level 1 I fixed that and ran it again. And voila! My phone ran it. All being very slow because it was that water demo one.
Woo hoo! Might be back to Qt for desktop and mobile app dev again.