...It adds a particle based fluid and soft body simulation to the rigid body functionality of Box2D. LiquidFun can be built for many different systems, including Android, iOS, Windows, OS X, Linux, and JavaScript. For applications on Google Play that integrate this tool, usage is tracked. This tracking is done automatically using the embedded version string (b2_liquidFunVersionString), and helps us continue to optimize it. Since this is open source, you are free to remove the version string but we would appreciate if you would leave it in.