With BOWDE, you can easily introduce slider just like Desmos, in order to fastly change parameters of your transfer functions.

To create a slider, introduce your new parameter in a transfer function like so:

The newly created button (here labelled "a") allows you to create the slider that will pop in your math bar when clicked:

The value can be changed directly by clicking on the parameter and writing your new value, or by sliding the slider.

Lower bound and upper bound of the slider can also be changed.