# RPN vs WP 31s

The clearest difference is price: WP 31s at Free against RPN's $1.99. WP 31s also leads on rating (4.9 vs 4.3) and review sentiment (100% vs 82%). RPN's advantage is update cadence (every 4 months vs every 10 months). On ratings volume, ads, in-app purchases and device support there is nothing between them.

WP 31s is free to download; RPN costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

WP 31s holds the better App Store score, 4.9 against 4.3. Both are backed by a comparable volume of ratings — 15 and 15 respectively. Written reviews point the same way: 82% of RPN's written reviews are positive against 100% of WP 31s's.

RPN ships an update every 4 months, WP 31s every 10 months. The most recent releases landed on October 20, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | RPN | WP 31s |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [4.3 (15 ratings)](https://appshunter.io/ios/app/rpn-45-sd/id509923051/reviews) | **[4.9 (15 ratings)](https://appshunter.io/ios/app/wp-31s/id973621300/reviews)** |
| Number of ratings | 15 | 15 |
| Positive reviews | 81.8% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 10 months |
| Monetization | Paid | **Free** |
| Size | 14 MB | 16 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [CuVee Software](https://appshunter.io/developer/424873503) | [Pascal Meheut](https://appshunter.io/developer/620255097) |

## What reviewers say

### RPN

[App page](https://appshunter.io/ios/app/rpn-45-sd/id509923051)

This app is a detailed simulation of a 1973 scientific calculator, offering a photorealistic interface and all original functions. It includes powerful enhancements for modern use, such as complex number support and advanced date calculations.

**Highlights:** Photorealistic calculator simulation, Full HP-45 function implementation, Complex number support, Advanced date and time functions, Printer simulation for calculation records, Stopwatch functionality, Cut/copy/paste display values

**Features:** macOS Compatibility

**In-app purchases:** none


### WP 31s

[App page](https://appshunter.io/ios/app/wp-31s/id973621300)

This app emulates a classic RPN scientific calculator, offering a rich function set for daily use with a simplified interface. It's based on the more complex WP 34s but is designed for easier operation.

**Highlights:** RPN scientific calculator emulation, Rich function set, Simplified, less cluttered keyboard, Based on WP 34s, Available on iOS

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is RPN free?

RPN costs $1.99, with no in-app purchases.

### Is WP 31s free?

WP 31s is free to download, with no in-app purchases.

### Which has better reviews, RPN or WP 31s?

WP 31s is rated higher. RPN averages 4.3 out of 5 from 15 ratings, while WP 31s averages 4.9 from 15 ratings.

### Do RPN or WP 31s have ads?

Neither RPN nor WP 31s shows ads.

### Which is updated more often, RPN or WP 31s?

RPN ships an update every 4 months, and WP 31s every 10 months. Most recently, RPN was updated on October 20, 2026 and WP 31s on October 24, 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.*