This completely free app with no ads has an intuitive interface
reminiscent of graphing calculators. It draws curves in four modes:
Cartesian Mode, showing the graphs of functions f(x) you specify, Polar
Mode, showing a circular polar grid and graphs of polar curves r(theta),
Implicit mode for graphing equations in x and y, and Parametric Mode for
curves of the form (x(t), y(t)). Easy-to-specify graph settings for
viewing important parts of graphs with the same "auto fit" feature you
find in graphing calculators, so you need specify only the domain xMin,
xMax (if you like) to see a part of a curve you are interested in.
Zooming in for a closeup of any part of the plane to see small details
clearly is easy with an intuitive and easy-to-control "zoom box." In
addition to the "trace" feature you may be used to from graphing
calculators, there is also a Table of values feature that allows to to
evaluate all the functions in your list for Cartesian and Polar mode at
whatever values of the independent variable you specify. The "Points and
Curve Fit" window can be used to add plotted sets of points to your
graph and also find a best-fit curve of any type you specify to model a
data set, also showing you r-squared and p-values for the fit.