The app 2D-Graphs offers the graphical representation of functional graphs of type f(x) or (x(t),y(t)). It comprises the computation of intersections, zeroes and extrema. One specialty is the development of the integral definition with a number of methods. Among these are upper and lower sums, trapeze and Simpson method, showing an approximation of the integral value. In addition the area betwenn two graphs can be calculated. For each graph, you may define a location, where the programme calcula