Those who grew up playing titles like 1942, Aero Fighters, or Space Invaders understand the beautiful simplicity of the shoot-'em-up genre of games, or the "shmups," as the E3 contingent might call them. In a shmup, you, a lone character, are tasked with obliterating an entire army of enemies, many of which attack from all directions. You are often piloting an airplane or spacecraft, and you are always armed with only the measliest of weapons to start off, making the job of upgrading your stock setup half the game's challenge, and, therefore, half the game's fun. The other portions of challenge and fun stem, of course, from the indiscriminate spraying of bullets and bombs.

These days, shmups, especially the vertically scrolling variety, are not as popular. However, we've found one that could very well help to revive the throwback genre, on a new and perfectly suitable platform: mobile devices.

Air Attack HD (download) is the shoot-'em-up aircraft game you dreamt of in your youth. It has beautiful 3D graphics, realistic physics, and a crazy-dramatic musical score that'll push your heart rate slightly above a healthy bpm level. There are upgradable cannons, flame throwers, homing rockets, tanks, ridiculously gigantic helicopters, and crater-making bombs, among other articles of video game warfare. And using your mobile device's touch screen, it's surprisingly simple and fun to maneuver your aircraft around. In fact, it seems like the mobile touch interface lends itself perfectly to the simple movements of the vertical-scrolling game, which is why we found Air Attack HD so entertaining and even addictive.

Air Attack HD is available for the Android platform in three different versions: Part 1, a free download comprising the first three stages; Part 2, a $1.95 download that opens up the next five stages; and the full version, which combines both parts in a single download for $2.94. If you're into shmups, or are just a fan of aircraft warfare in general, we highly recommend downloading Air Attack HD (rather than engaging in actual aircraft warfare).