Fun concept! The countryball characters and battle animations are entertaining, and there's a nice variety of strategic options.
I think the game could benefit from a soundtrack with a little more tension and excitement.
I also noticed a small UI issue while playing on my computer. The panel showing Treasury, Income, Units, and Safe sometimes covers the Attack button when selecting countries on the map. It happens with some countries but not others, making the button difficult or impossible to see.
Hope this helps!