Good news everyone !
Besides 3D Graphs that draws functions with (x,y) as parameters, you are now able to view implicit surfaces of a function in a graph with MathTouchBook ! Surfaces are then defined by space functions with (x,y,z) parameters, and will draw a skin where the value is zero ! Optional parameter t stands for time and will allow to animate anything as you can see in the Video.
A special method for computing values were used: more than 200 000 calls must be done through the whole graph of each function when the shape changes, and the CPU can hardly do that. The solution was to reuse the OpenGL Shading Language (GLSL) function exporter: It translates the function into a source that can be compiled directly with OpenGL drivers, so it is executed 1000 times faster by the Graphical Processing Unit (GPU) of your Smartphone or Tablet.
The new update also brings a better keyboard , with fractional numbers, and many improvements and corrections.