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RPN Calc app for iPhone and iPad


4.0 ( 3920 ratings )
Utilities Productivity
Developer: James Mattis
0.99 USD
Current version: 9.0.3, last update: 7 years ago
First release : 12 Jul 2008
App size: 4.23 Mb

A simple reverse polish notation calculator loosely based on my trusty HP-32SII that runs on iPhone, iPad, and Apple Watch!

If you are familiar with HP RPN calculators, the operation of this calculator should seem very straightforward - albeit simplified. It cant be programmed, and it doesnt handle binary, or hexadecimal numbers.

But, it has a clean, simple interface with large, easy to press buttons. It has all of the functions required for quick calculations when your iPhone is handier than your computer or calculator.

And, remember those cool calculator watches from the 1980s? Unfortunately, none of them were RPN. RPN Calc brings a reverse polish notation watch calculator to the Apple Watch!

In addition to the standard RPN Calculator app that runs on iPhone, iPad, and Apple Watch, RPN Calc includes a handy micro RPN Calc Today Extension available for convenient access to quick calculations from the pull down Today screen.

Latest reviews of RPN Calc app for iPhone and iPad

Not working properly
Not working in Europe 5,50 Enter 6 + Result 11,0
Unable to enter a number. Unable to add up.
I have tried all the of ways I can think of to enter the number 123E-6 without success. The obvious key sequence of 1, 2, 3, E, 6, plusMinus leads to -123E6. The less obvious 1, 2, 3, E, -, 6 leads to nothing useful. Also the calculator does actually seem to work. Starting from a clear calculator, enter 1, 2, 3, +, + I would have thought that the answer would be 6. Its actually given as 7. This would imply that the calculator only have X and Y registers: no Z!
Great Start
I had the same problem with the 1,2,3, E -6, but 1,2,3, +,+ did give me 6 as expected.
Nice Layout and Appearance
Nicely done RPN layout. Could use a "click sound" option, and some financial calc options wouldnt hurt either. One issue is that when using fixed decimal (say 3,4, or 5), it reverts to sci/exponent view long before the available characters are used up. Kind of annoying. Fix that and its 5 stars.
A very good and handy app!
With respect to RPN and scientific functions this is a very adequate app. I like that log as well as inverse and hyperbolic trig functions have been included. Counter so some reviews its always worthwhile to have an extra calculator--that extra being a scientific _RPN_ calculator
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