iPodtouchfans.com forum member Virtualball has compiled a version of Pyro Sand for the iPod Touch/iPhone. The game involves four different particles falling from the top of the screen, which all look and move similar to sand. The particles resemble sand, water, salt, and oil in color. Along with these four, additional elements can be placed on the screen with your finger by choosing the colored icons below, some that are solid and stationary instead of flowing. By mixing the different elements together, many colorful designs, complex structures, and systems can be created.

http://www.iphoneskinning.com/2007/12/pyro-sand-for-iphone.html