Autodesk's Fluid FX for iPhone claims to bring the "excitement of Hollywood visual effects" to your iDevice (it's a universal app, though this review is based on the iPhone version). Based on Autodesk's award-winning fluid-dynamics program, Maya, the Fluid FX app allows you to manipulate images using a variety of effects. It's a fun timewaster, but the user interface is frustratingly unintuitive which makes this novelty app even less useful.
Fluid FX comes with a number of preset images for you to play with, ranging from faces of the developers to animals. The real fun comes when you add effects to these images. Based on which effect you have selected, you can make fireballs dance across the screen, swirl and inflate the photo you're editing, or create ghostly lighting effects that vanish like smoke. Watch the video; it's worth it.
Unfortunately, the full potential of Fluid FX is severely hampered by the user interface. It's remarkably unintuitive, and there's no tutorial. It took me forever to figure out how to pick ONE preset image instead of having the app scroll through them all while I was editing.
Fluid FX is still a fun time-waster, but...well, you don't want to waste your time, in a time-waster app, trying to figure out the controls. Besides that, Fluid FX is just a novelty, albeit an entertaining one that can create some nifty pictures. Until the interface is improved, I'd recommend passing on this one.