# RPN-38 CX — Great classic calculator

> Photo-realistic simulation of HP-38C programmable business calculator for iPhone. (iPhone/iPad app by CuVee Software.)

- Source: https://appshunter.io/ios/app/rpn-38-cx/id1082636662 (this page in markdown: same URL + `.md`)
- Developer: [CuVee Software](https://appshunter.io/developer/424873503)
- Category: Productivity, Finance
- Price: $1.99
- Rating: 5.00/5 from 6 App Store ratings · 4 written reviews indexed
- Age rating: 4+
- Requires: iOS 12.0 · 12 MB
- Languages: American English
- Released: 2016-02-18
- Data updated: 2026-08-03
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/rpn-38-cx/id1082636662/reviews.md

## What is RPN?

RPN-38 CX is the first photo-realistic simulation of Hewlett-Packard's popular high-end programmable business calculator HP-38C for the iPhone. Produced from 1979 through 1983, it was the "Chive" member of the third-generation HP calculators known as the "Spice" series.

While the simulator works like the original calculator, a number of carefully designed extensions make it a lot easier to use.

RPN-38 CX is fully compatible with the HP-12C, except for calculations and programs involving Bonds and Depreciation.


Features:

• Photo-realistic look-and-feel
• Programmable (99 steps, program memory not shared with register memory)
• Subroutines, flags, loop control, extended conditional branching
• Insert and delete steps with automatic address correction
• 20 registers, "continuous", with unlimited store/recall arithmetic
• Indirect register addressing
• Register view
• Program listing view
• Program library view
• Additional functions (nominal and effective interest rate)
• Shortcuts for often-used key combinations
• Store and retrieve any number of programs
• Sharing: e-mail, AirDrop, Dropbox, copy, paste, print
• 40 programs pre-installed

Calculator functions:
• Percentage (%, ∆%, %Total)
• Simple and Compound Interest
• Optional odd periods (like HP-12)
• Nominal/Effective interest rate conversion
• Amortization
• Discounted Cash Flow Analysis
• Net Present Value, Internal Rate of Return
• Date and Calendar (actual or 30/360 day basis)
• Statistics (mean, weighted mean, standard deviation)
• Linear Regression
• Additional functions not found on the HP-38:
- Subroutines, flags, loop control, random number, Pi, Log, x² and more

Details: cuveesoft.ch/rpn38

## Key features

- Photo-realistic look-and-feel
- Programmable with subroutines and flags
- 20 registers with unlimited store/recall
- Indirect register addressing
- Program library and sharing
- Financial and statistical functions
- Date and calendar calculations

## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/rpn-38-cx/id1082636662/reviews.md

### 5/5 — I love it !

*2019-02-10*

For a financial person, this is as good as it gets.  I've always loved the vertical format of the HP-38 and the red LED.  This is about as perfect an emulation of the original as one could ask for.  This one adds many extra features, like subroutines and flags, and is so easy to program.  Accuracy is perfect and I love that I can save and load programs and constants as well.  Great job, Mr. Kunz!!!

### 5/5 — That is almost as good as original!

*2019-01-30*

I have not used this particular model, but others either side and you have captured the essence of the product and its efficiency. Have to look at the others now.

### 5/5 — Rechnen können sie alle

*2019-01-16*

und dieser Rechner zeigt auf sympathische Weise, dass HP schon in den 1970er Jahren überaus leistungsfähige Taschenrechner angeboten hat.

### 5/5 — Hervorragender Emulator/Best HP Calc Package

*2017-01-23*

Habe selber einen HP31E und HP41C und war froh als ich dieses Paket mit den beiden HP32/38 Rechnern fand. Wäre schon super wenn es allein die Funktionen anbietet, aber so ist es noch besser, da man Programme aus dem Rechner verwalten, speichern und laden kann. Der HP32 ist erweitert, so dass man ihn auch programmieren kann und auch der HP38 kann sogar Funktionen des HP12C emulieren.
Der Entwickler antwortet schnell - alles eine runde Sache.
----
I own a HP31E and HP41C and was happy when I found this package with the two HP32/38 calcs. Even for having just the functions of the original would be superb, but these do organize your programs out of the calculator, save and load them. The HP32 is extended, so you can program it, and the HP38 does emulate some functionality of the HP12C. The developer answers timely - all in all a safe deal.

## Frequently asked questions about RPN

### What is RPN-38 CX?

RPN-38 CX is a photo-realistic simulation of the classic Hewlett-Packard HP-38C programmable business calculator for iPhone and iPod Touch. It replicates the original functionality with added extensions for ease of use.

### Is RPN-38 CX compatible with the HP-12C?

RPN-38 CX is fully compatible with the HP-12C, except for calculations and programs involving Bonds and Depreciation. It offers many similar functions and programming capabilities.

### What programming features does RPN-38 CX offer?

RPN-38 CX supports 99 steps of program memory, subroutines, flags, loop control, and extended conditional branching. It also allows inserting and deleting steps with automatic address correction.

### How many registers does RPN-38 CX have?

RPN-38 CX features 20 registers that are 'continuous' and offer unlimited store/recall arithmetic. It also supports indirect register addressing and a register view.

### Can I share programs with RPN-38 CX?

Yes, RPN-38 CX allows you to store and retrieve any number of programs. You can share them via email, AirDrop, Dropbox, copy, paste, or print.

### What financial functions are included in RPN-38 CX?

RPN-38 CX includes functions for simple and compound interest, nominal/effective interest rate conversion, amortization, discounted cash flow analysis, Net Present Value, and Internal Rate of Return.

### Does RPN-38 CX have ads?

No, RPN-38 CX is a paid application and does not contain advertisements. Users can enjoy an uninterrupted experience.

### How often is RPN-38 CX updated?

The latest version, 4.2, was last updated on October 15, 2025. Updates typically include bug fixes and feature enhancements to improve the user experience.

## Version history (last 5 releases)

### 4.2 — 2025-10-15

• Improved compatibility with iPhone Air and iOS 26.

### 4.1 — 2025-07-25

Non-volatile stack: when reloading the app, the stack is now restored along with all registers.

### 4.0 — 2025-05-08

• Faster startup – no delay until the first button press is recognized after switching on.

### 3.9 — 2024-10-22

• Added warning when attempting to replace a Sample Program.

• Visual adjustments to iPhone 16 Pro and iPhone 16 Pro Max

### 3.8 — 2024-01-15

• Internal optimizations and cleanups.

• Modified info screen to avoid clipping by the Dynamic Island.

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## More apps by CuVee Software

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All apps by CuVee Software: https://appshunter.io/developer/424873503

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-03.*