# RPNPro vs RPNu

The clearest difference is update cadence: RPNu at every 2 months against RPNPro's every 37 months. RPNPro's advantage is iOS requirement (9.1 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

RPNPro ships an update every 37 months, RPNu every 2 months. The most recent releases landed on October 14, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | RPNPro | RPNu |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/rpnpro/id603155368/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 37 months | **Every 2 months** |
| Monetization | Free | — |
| Size | 1 MB | 49 MB |
| Requires iOS | **9.1** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Felix Meier](https://appshunter.io/developer/603155771) | [Scott Johnson](https://appshunter.io/developer/580251998) |

## What reviewers say

### RPNPro

[App page](https://appshunter.io/ios/app/rpnpro/id603155368)

This calculator utilizes Reverse Polish Notation (RPN) for input, mirroring the functionality of classic HP calculators. It features a four-level stack with X, Y, Z, and T registers, displaying the X register in decimal, hexadecimal, and binary.

**Highlights:** Reverse Polish Notation (RPN) input, Four-level stack (X, Y, Z, T registers), Decimal, hexadecimal, and binary display, Modeled after HP calculators, Designed for software engineers

**Features:** macOS Compatibility

**In-app purchases:** none


### RPNu

[App page](https://appshunter.io/ios/app/rpnu/id1195709318)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is RPNPro free?

RPNPro is free to download, with no in-app purchases.

### Is RPNu free?

RPNu is free to download, with no in-app purchases.

### Do RPNPro or RPNu have ads?

Neither RPNPro nor RPNu shows ads.

### Which is updated more often, RPNPro or RPNu?

RPNPro ships an update every 37 months, and RPNu every 2 months. Most recently, RPNPro was updated on October 14, 2026 and RPNu on October 26, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*