Take a look at this cool little app that has been developed by Peder Norby from Trapcode. As well as the incredible plugins that Trapcode produce for After Effects, Peder has also written a few apps for the iPhone / iPad that are definitely worth checking out.
In Peders words “Vortex.A – touch-interactive generative art. I am experimenting with fluid dynamics: how liquids and gases behave – a classically difficult problem in physics/maths. Most agree that fluid dynamics is described by the Navier-Stokes differential equations. There is no known all-case solution for the equations, but there are solutions for specific cases and approximative methods to find numerical solutions.” – For more info, you should check out the Trapcode -Blog.
You can buy the Vortex.A app here