This should work with recent desktop versions of Chrome or Firefox and hopefully also with a stylus or your finger. It was coded using Vanilla JS.
You are seeing two copies of the complex plane. The left half is for the arguments of a certain function (displayed in the small rectangle above) and the right half shows the corresponding function values.
You can draw or click in the left half (or just move the pointer around) to see the effects on the right.
You can use the arrow keys to move the part of the plane you're seeing and you can use the
Page Up and Page Down keys
to zoom in or out. Use l and r to
switch between the two halfs.
Use f or F to select different functions.
0 resets everything and 0 clears the screen.
used to undo the last drawing action.