3. Samurai II:Vengeance
If you love all those swords and samurais then you should consider playing Samurai II on your iPhone. You can cut heads and hands in this game with blood all over the floor along with your activated adrenaline. The game is updated regularly with more and more enemies to be beheaded with newer and more powerful weapons.
Also, Samurai II can be a perfect example of 3D games for iPhones when you experience camera rotation and shading during gameplay. Violent iPhone games are very popular these days and as it seems in a constant rise.