iEngCalc app for iPhone and iPad

iEngCalc is a scientific or engineering calculator.
The calculator you can trust for every calculation.
Accurate calculation results. (significant to the last digit)
For every calculation result you can trust the result to the last digit.
The exact value of sin(1E100) is "-0.3723761236612766882620866955316…".
For sin(1E100) this calculator produces the result "-3.7237612366127668826E-1" by rounding the above exact value to 20 signifiant digits.
Check if your calculator produces the correct results for the following expressions.
3.456^2-1.727*1.729*4 = 4.E-6
3.456^2-1.727*1.729*4-4.E-6+1.E-10 = 1.E-10
0.8-0.5-0.3 = 0
1.E-12+0.8-0.5-0.3 = 1.E-12
(1+1/1E100)^(1E100) = 2.718281828459045235…
(3^(1/1E10))^(1E10) = 3
sin(pi*1E10+0.1) = sin(0.1)
sin(1E100) = -0.3723761236612766882620866955316…
if you want a calculator that produces correct results for all the above expressions this one is for you.
Correctly rounding the exact value.
The rounding mode for half way cases can be chosen between "Round Half Up" and "Round Half to Even".
Create custom functions with multiple arguments.
Create named variables for storing any values.