4.25 seems to have fixed some android boot issues I was having but drawing tiles (C++) with custom materials has the vertex Y positions inverted on Android.
Some example code below (this works on PC):
bool DrawMaterialInArea(UCanvas &Canvas, const FLinearColor &color, const UDynamicMaterial* RenderMaterial)
{ ....
FCanvasTileItem tileItem(
topLeft, RenderMaterial->GetRenderProxy(),
size
);
tileItem.SetColor(color);
tileItem.UV0 = topLeftUV;
tileItem.UV1 = bottomRightUV;
//tileItem.MaterialRenderProxy = RenderMaterial->GetRenderProxy();
Canvas.DrawItem(tileItem);