Honestly plotting arbitrary 2D equations/inequations (groups) and parametric equations. Equation Sketchpad graphs all kind of equations with unparalleled accuracy and speed. Supports a wide range of operators and functions not limited to elementary math. The responsive user interface allows interactive tuning of user defined parameters.

Supported operators are:

• • • / ^ %
      < > >= <= = !=
      &(and) |(or) !(not)

You can use logical operators to combine multiple equations and inequations together to create a complicated graph.

Supported built-in functions include:
sin, cos, tan, cot, sec, csc,
asin, acos, atan, acot, sinh, cosh, tanh,
log, log2, log10, exp, sqr, sqrt
abs, floor, ceil,
min, max,
gamma, fact

Technical details:

This app is designed for maximum accuracy and performance. Equation Sketchpad is able to accurately plot extremely complex equations(e.g. screenshot 1) that cannot be graphed correctly by most other tools. The graphing engine features a highly parallelized implementation of interval based algorithm that is capable of efficiently handling all kinds of difficult cases such as discontinuity and extreme variation. Direct2D is used as presentation API for smooth user experience.

Trial version has no time or functionality limits except that equations are limited to 30 characters in length. I need your support to make it even better!

For comparison of graph quality, you may try plotting the following equation in other tools and refer to screenshot 1:
(x/sin(x)+y/sin(y)+xy/sin(xy))(x/sin(x)+y/sin(y)-xy/sin(xy)) (x/sin(x)-y/sin(y)+xy/sin(xy))(x/sin(x)-y/sin(y)-xy/sin(x*y)) = 0