XPP is an app for solving differential equations, delay equations, functional equations, boundary value problems, and stochastic equations.It is based on the popular program XPPAUT and uses the same ODE file syntax. The interface has been completely rewritten for the iPad.XPP will draw nullclines, direction fields, and two- and three-dimensional plots of solutions as well as find equilibrium points, their stability and separatrices. Users can choose from a dozen different numerical integrators. Computed data can be exported via iTunes. Using the sliders, it is possible to watch how the behavior of the system changes as parameters vary. Solve all your differential equations problems with XPP.Add any of thousands of equations to your library directly from the WWW or import via iTunes.