Scroll or pinch to zoom. Keys: press A or B to pick the center or the input. Press [ or ] to step through the handles. Press ← or → to move it one step. Hold Shift with an arrow key to move it five steps. Press Esc to let go.
Function and center
Write it as in R: exp(2*x), x^(1/3), log(x). A makeFun line works too.