PiSquared app for iPhone and iPad

PiSquared is an RPN-only calculator for the Apple Watch. It supports a wide variety of mathematical and scientific functions as well as binary operations for programmers. Integer, floating point (real) and complex numbers are equally supported.
These functions are available:
- calculation of the number of combinations or permutations for integer numbers
- factorials for integer numbers or Gamma function for positive non-integer numbers
- trigonometric, logarithmic, exponential and hyperbolic functions for floating point and complex numbers
- date and time conversions
- logical operations for binary, octal or hexadecimal numbers
- cartesian to polar coordinate conversions and vice versa (floating point numbers)
- degrees to radians and vice versa conversions (floating point numbers)
- absolute, integer and fractional value of a number (floating point and partially complex numbers)
- rounding of a real number (standard rounding and rounding up or down)
- random number generator
and some more.
The calculator has a stack depth of ten and features ten additional storage registers. All storage registers and the stack can be inspected. The stack itself can be manipulated by moving it up or down or by swapping its two topmost elements.