I think I may have just stumbled upon the greatest shoot-em-up experience on the iPhone. In case you didn’t catch Meg’s post on Sketch Nation Shooter, this dollar app lets players take control and create their own shmup game. I like to think of myself as visually impaired: You see, I make music and can easily work with sounds. But the moment I pick up a pencil and attempt to draw, what comes out looks even more atrocious than a ridiculously hideous abstract painting. That’s why all of these DIY experiences (ironically enough) don’t bode well with me. I’m a gamer; I game. It’s hard enough for me to make time for gaming, how the hell am I going to be able to create my own game? Well, with Sketch Nation Shooter, it’s relatively simple.

Engineous Games have authored a step-by-step process that will enable literally anybody to create something. What’s best is that since Sketch Nation Shooter is actually fun, that’s reason enough to warrant your own creation. And who didn’t believe in user-generated content? After logging in through the Facebook integration, you’ll be treated to a whole slew of downloadable Sketch Nation games that other eager iPhone owners have created. These are usually themed, such as the “I’m On a Boat” level that I snagged up last night.

Unfortunately, at the moment, there’s no method of searching for titles. Instead, you’ll have to sift your way through each page of content and download whichever games your heart desires. Don’t take Sketch Nation lightly, however, as the games–including the ones that come equipped from Engineous Games–are rather difficult. In fact, some user-generated levels choose to capitalize on this and advertise themselves as incredibly tough.

Sketch Nation Shooter provides you with two methods of creating your own shmup. The first is Simple Mode, which is what I used to create a game entitled “Gimme 20 dollas!” (mimicking the stupefying hip-hop track of the same name from Ron Browz). Simple Mode just had me draw up the main character and enemies on a piece of paper and take pictures of both with my iPhone–all of which was done seamlessly in-game. Sketch Nation will then take whatever shape you’ve designed and place it in the game. If you want to assume direct control over your work, however, you can use Advanced Mode–which offers much more customization. Do you want to add a boss to your game? Maybe you’d like to design the level set pieces yourself? Want to increase or decrease pacing?

While Simple Mode and Advanced Mode each offer a worthy experience to the creator, they still leave a few details unattended. For example, Sketch Nation gives you ten tracks to choose from for music…but since I’m using my iPhone, wouldn’t it be better to let me select a song from my iTunes library? Yes, this proves problematic when put online but what if it’s just for personal use? Certainly, this can be fixed by a future update but until then users are tied up to what the current build has to offer. Regardless of the nit-picking, however, Sketch Nation Shooter is ultimately a unique experience that flows surprisingly smoothly. It took me just a few minutes to create my own shmup and that was only because I’m terrible at drawing.

For $0.99, you’re buying an app that truly encourages creativity from its users. And by the looks of it, the do-it-yourself agenda is catching on. Sketch Nation Shooter is currently in the Top 50 Paid Apps across iTunes and it deserves to be there. Don’t expect this to be the last time user-generated content takes the stage.

Check out the Sketch Nation community.