GO-25 SciRPN simulates the venerable HP-25C Programmable Scientific Calculator. The HP-25C was released in 1976 and sold for a MSRP of $195. Virtually indistinguishable from the real item in operation, GO-25 is a powerful yet simple retro calculator.

•Requires iOS 4.3 or higher
•RPN
•Copy / Paste
•Shake to clear X
•Programmable with 99 program steps, conditionals, full-speed or single step operation
•Built-in library of sample programs
•iTunes File Sharing
•Swipe-up gesture that displays the stack and memory registers, and the program listing views
•For iPad two finger drag operations for displayed views
•Addition, subtraction, multiplication, division
•Trigonometric functions : sin, cos, tan, sin⁻¹, cos⁻¹, tan⁻¹, degrees, radians or grads
•Rectangular/polar coordinate conversion
•Hours, minutes, seconds to decimal degrees conversion, and vice-versa
•Logarithmic functions : log, 10**x, ln, e**x
•Summation Σ+, mean, standard deviation
•Other functions : Y**x,1/x, √x, π, FRAC, INT, ABS, %
•Display : LED, 10 significant digits (8 + 2 digit exponent in scientific notation), 10-99 to 10+99
•Memory : 4 register stack, stack roll down, X-Y interchange, 10 memory registers with register math
•Optional thousands separator