Quick Graph, available on the iTunes App Store, is an advanced graphing calculator, both in 2-D and 3-D.
The app uses an intuitive interface that makes it easy to enter and/or edit equations and visualize them in mathematical notation. It can display explicit and implicit equations, as well as inequalities in both 2-D and 3-D, in all standard coordinate systems: cartesian, polar, spherical, and cylindrical. These graphs can be copied, e-mailed, or saved to the device's photo library.
Price: Free or $1.99 for the expanded version.
