The systems activity allows you to plot the solutions to a system of up to six ordinary differential equations.  The initial condition for each equation can be input just to the right of the equation.  This activity is different from phase planes because it allows you the equations to explicitly depend on the independent variable t as well as the dependent variables x,y,z,u,v and wYou can resize the window using pinch and pull gestures as well as extend the solutions by panning with a single finger.  Enter your own equations or explore one of the preloaded systems.