Took me a few tries to learn the timing but after that I was knocking down warheads like a pro. Highly recommend this to anyone wanting that old school arcade experience on iOS. Everything works so well. The colors are bright and crisp. One touch controls are responsive. Very enjoyable experience. As you defend your cities coins will appear which you use to improve your shields and improve your missiles. Yes you can buy coins but its unnecessary as coins drop in gameplay with enough frequency for you to upgrade your ships.
I'd love to see an update where you don't loose your bank after closing your app. That's all. Other than that this is a real treat and a great homage to a classic that really recreates the arcade experience. Grab it!