RPN User Reviews

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  • Highly Recommended!

    I love this app. I bought a HP 45 while in college. If I am not mistaken, it costed more than $350. I am of the generation that learned both slide rule and calculator. I would not be able to graduate without my HP 45. I still have it stored somewhere in a box. I am so used to RPN calculators that I have to think when I use a normal calculator. I recently got an iPad Air 4 and was looking for a calculator app. So happy to find this one. I am amazed that I still remember how to work this. Considering that I have long retired and have not use a scientific calculator for many years. A financial calculator would probably be more useful but then it would not put a BIG smile on my face when I am using this HP 45 app.
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  • delta dates using a register recall.

    the recall of a stored number is trunked
    I stored 12.312017 in register 9. when I recalled it it came back as 12.3120 the recall trunked the last two digits. ignore this entry user error.
  • Great simulation of a classic hp rpn calculator

    I have been using this app for several years. I still have one of the original HP 45 calculators. Has it really been 45 years? This App is my go to calculator. Highly recommended.
  • Fantastically faithful hp-45

    This app is beautifully executed in every way, my sincerest compliments to the authors. I owned the hp-35, 45 and 65 and it's great to have one of them "back" again.

    My only request: save state between program executions.
  • So much to love with this app !

    This app is a great emulator of the classic HP-45 Scientific Calculator, in look, feel and function. It keeps getting better and better with each update. It offers full complex number functionality, even surpassing that of the HP-15 in complex mode. It comes with many powerful functions, which are actually sophisticated programs, including: 1. Linear Equations -- this lets you solve simulatneous equations for X & Y and in complex mode can solve for the real and imaginary parts for X & Y. 2. Quadratic Equation Solver -- solves entirely within the stack. 3. Cubic Equation Solver -- solves entirely within the stack. 4. The Factorial (n!) also doubles as a gamma function. By subtracting 1 from X and pressing n! you can get the gamma function of any positive or negative number and not just integers. 5. It offers full Linear Regression & Linear Estimate and many other statistical functions. 6. Full calendar, clock and timer functions. An alternate view shows full contents of stack, last-X and all 18 numbered registers, and in complex mode you can see both the real and imaginary parts of all stack & last-x registers. While the original HP-45 had 10 digit accuracy, this app has much greater accuracy as it carries far more digits in its internal calculations. This app is a companion to RPN-45 SD (for iPhone). I have both and highly recommend buying BOTH versions so you get the extra benefits of the iPad version and the portability of the small device version. Truly elegant design. I love the quality of cuveesoft's calculators!
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  • Beautiful

    A great simulation of the HP-45. Beautifully made, with a lot of attention to small details.
  • Nice update

    ENG is a good addition. Some suggestions for the future:

    Swiping the calc could show the guide on the back of the real calculator.

    Show views of the innards somewhere in the Help.

    Support financial calculations (n, i, pv, pmt, fv). The tricky part will be selecting which keys to use.

    Show more constants and conversions.
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  • My go-to calculator

    I have no idea where all the one star reviews are coming from (perhaps the initial release?). If you have fond memories, as I do, of using Hewlett Packard scientific calculators back in the seventies and eighties, you owe it to yourself to check this app out. It isn't a programming heavyweight like some of the other vastly more expensive simulations, but it offers a straightforward presentation that makes you feel like you have your old trusty HP-45 back on your desk, but one that's been enhanced too.

    Five stars for presentation, functionality, and continuous improvement.
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  • It just gets better

    I thought this was great before. I had only three suggestions and they've all been implemented. Great job.
  • Works great!!!

    Key pad works much better now. Look forward to exploring the new functions. Thanks!

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