Hills of Glory 3D is a riff on the tower defence template. You need to stop enemy soldiers from destroying your base with an increasingly powerful arsenal.
You start off with just a gun, but soon you're firing mortars, unleashing napalm-dropping helicopters, and calling in enormous air strikes.
The controls are simple but intuitive, making the most of the multi-touch capabilities of modern smartphones.
It's not the best looking game, and it's not the most original, but its bursts of war-time violence will keep you entertained.