Graph is described as 'open source application used to draw mathematical graphs in a coordinate system. Anyone who wants to draw graphs of functions will find this program useful. The program makes it very easy to visualize a function and paste it into another program' and is an app in the Education & Reference category. There are more than 25 alternatives to Graph for a variety of platforms, including Windows, Mac, Linux, Online / Web-based and iPhone. The best alternative is R (programming language), which is both free and Open Source. Other great apps like Graph are GeoGebra (Free), SageMath (Free, Open Source), Matplotlib (Free, Open Source) and Microsoft Mathematics (Free).
Grapheme is an intuitive and powerful data visualization and analysis tool. Grapheme brings you advanced data analysis capabilities along with interactive plotting functionalities to enable exploring and understanding complex sets of data.
WordMat is an add-on to Microsoft Word which creates a tab with math functionality. Part of the Math functionality is provided by other open-source applications like Maxima, GeoGebra, Graph and GnuPlot.
pro Fit is a Macintosh (Mac OS) application for data/function analysis, plotting, and curve fitting. It is used by scientists and engineers to analyze their measurements and the mathematical models they use to describe them.