This app calculates the analytic formula of the first derivative of a given function. Derivative represents a rate of change of a function with respect to an independent variable. This app enables to differentiate a function that depends on more than one independent variable (called here a multi-parametric case) by considering these variables separatelly. To do so, one must declare a name of independent variable with respect to which a given function is differentiated. During differentiation, the rest of variables is kept constant. The derivative found on the basis of the obtained analytical formula can be compared with the derivative found numerically. The obtained results can then be depicted in plots. In order to plot a multi-parametric case, all remaining independent variables must be set by the user. To make this app more didactic, it is possible to track and practise intermediate stages of searching for the analytic derivative. All these steps can be performed by the user himself. In this way, the final formula of the derivative sought will become more understandable.