You may known of my penchant for tower defense games, but I also have a not-so-secret love for arcade scrollers. The good news for your time-sucking pleasure is that I found a new one called Photon Strike. It’s a solid vertical scroller for iPhone an iPad (I played on iPad) with good graphics and fast action. In fact, it’s very fast. It’s similar to others in the genre. You have to steer your ship (with your fingers), firing as long as your finger is on the screen. Waves of enemies fly around the screen, and you have to shoot/avoid them. Powerups are available throughout each level, and you get credits for each enemy you destroy for buying upgrades. It’s free to download, but for real-world cash, you can get yourself a whole heap of credits. You can also watch videos for free credits. Every five waves there’s a boss at the end. It’s ad-supported, but the ads go away with any purchase (the ads are not obnoxious).  That said, this is the kind of game where I’m happy to pay to unlock ads to directly support the developer.