The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
From Clever Alien:
The EQ7 is a professional, accurate, full-featured scientific calculator designed for the iPhone, iPod touch, and iPad. It offers the powerful features of a handheld calculator, with an improved interface to enhance user experiences. While designed primarily for mathematicians, engineers, and students, this calculator is accessible to anyone.Features: Large multi-lined display with automatically adjusting font size for long equations Morphing keyboard that accommodates user needs Equation history Store favourite equations Display answers as fractions and mixed numerals Assign variables and constants Switch bases: binary, octal, decimal, and hexadecimal Complex numbers Conversions Trigonometry Probability Generate random numbers Calculus (integration, and differentiation) Solving equations (determine the x value which reduces the equation to zero) Euclidean and floored division modulus Greatest common divisor Least common multiple Average Median Series Product of a sequence of terms Sign (sgn) Sexagesimal (degrees, minutes, seconds) Polar and rectangular coordinates Configurable rounding mode for displayed answers Radians, degrees, and gradians Normal, scientific, engineering, and fixed notation Full help documentation (click the advanced button entitled "help")