GO-21 SciRPN
GO-21 SciRPN simulates the venerable HP-21 Pocket Scientific Calculator from 1975. Virtually indistinguishable from the real item in operation, GO-21 is a powerful yet simple retro calculator.
GO-21 combines the classic behavior of the HP-21 with modern iPhone capabilities like key click sounds, visual touch feedback, persistent stack, memory and display format, and help information.
• Requires iOS 4.3 or later
• RPN
• Copy / Paste
• Shake to clear X
• Swipe gestures that roll and display the stack
• Addition, subtraction, multiplication, division
• Trigonometric functions : sin, cos, tan, sin⁻¹, cos⁻¹, tan⁻¹, degrees or radians
• Rectangular/polar coordinate conversion
• Logarithmic functions : log, 10**x, ln, e**x
• Other functions : Y**x,1/x, √x, π
• 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, manual memory with register math
• floating stack and memory window
What's new
GO-21 SciRPN update 3.10 is recommended for all users and improves performance, reliability and usability, including:
- On iPad an alternate way to display and hide the stack information views is to double tap the display. For iPod and iPhone this works to display the information view, but dismiss it with the usual swipe-up gesture.
Screenshots
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- Last changed:
- 1 day ago
- Category:
- Utilities
- Developer:
- BigCatOs
- Version:
- 3.10
- Average Rating:
- 4.50 (15)
- Size:
- 6.0 MB












