1)   ZGrapher 1.4
This graphing calculator can plot y(x), x(y), polar, parametric and table-defined functions. Calculus features include obtaining derivatives, equations of tangents and normals, numerical integration, regression analysis.
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 2)   Harmonix 1.1
With the Harmonix PhotoShop plug-in you can draw complex wave lines build by mixing harmonic frequencies. Useful for quickly generating oscilloscope or heartmonitor display, graphs or to play around with the concepts of harmonic frequency mixing.
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 3)   ZigZag 1.1
ZigZag is a handy tool to plot and explore math functions. It can plot Cartesian (Y(x) and X(y)), polar, parametric and also table-defined graphs
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 4)   FlatGraph 1.10b2
Plotting functions (usual and parametric) with more possibilities. Differentiation of any order (with simplification). Construction of tangents to the graph. The simple and clear interface with detailed documentation and examples of work.
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