Hi..
I try export .apk from your .c3p in github. I face same result, both also has black bar at below..
is it because of the viewport 720x1980 ("720p landscape" or "720p Potrait") ?
But if I make a new blank project and choose viewport 480x854 ("SD landscape 16:9" or "SD portrait 9:16") it will perfectly full screen without black bar