# RPN vs DB40X

The clearest difference is price: DB40X at Free against RPN's $1.99. DB40X also leads on rating (4.7 vs 4.3) and update cadence (every 3 weeks vs every 4 months). RPN's advantage is review sentiment (82% vs 67%) and iOS requirement (12.0 vs 14.0). On ratings volume, ads, in-app purchases and device support there is nothing between them.

DB40X is free to download; RPN costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

DB40X holds the better App Store score, 4.7 against 4.3. Both are backed by a comparable volume of ratings — 15 and 7 respectively. Written reviews complicate that: 82% of RPN's written reviews are positive against 67% of DB40X's, so the app with the better star average is not the one people write more warmly about.

RPN ships an update every 4 months, DB40X every 3 weeks. The most recent releases landed on October 20, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | RPN | DB40X |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [4.3 (15 ratings)](https://appshunter.io/ios/app/rpn-45-sd/id509923051/reviews) | **[4.7 (7 ratings)](https://appshunter.io/ios/app/db40x/id6624315901/reviews)** |
| Number of ratings | **15** | 7 |
| Positive reviews | **81.8% of reviews** | 66.7% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 weeks** |
| Monetization | Paid | **Free** |
| Size | 14 MB | 7 MB |
| Requires iOS | **12.0** | 14.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [CuVee Software](https://appshunter.io/developer/424873503) | [Christophe de Dinechin](https://appshunter.io/developer/1761608161) |

## 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


### DB40X

[App page](https://appshunter.io/ios/app/db40x/id6624315901)

A high-precision scientific calculator inspired by the HP48 series, offering arbitrary precision computations, complex numbers, vectors, matrices, and graphing. It supports RPN and algebraic operations, with over 1000 built-in functions and a hyperlinked help system.

**Highlights:** Arbitrary precision computations, RPN and algebraic operations, Complex numbers, vectors, and matrices, Graphing and plotting, Engineering units and conversions, Hyperlinked help system

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is RPN free?

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

### Is DB40X free?

DB40X is free to download, with no in-app purchases.

### Which has better reviews, RPN or DB40X?

DB40X is rated higher. RPN averages 4.3 out of 5 from 15 ratings, while DB40X averages 4.7 from 7 ratings.

### Do RPN or DB40X have ads?

Neither RPN nor DB40X shows ads.

### Which is updated more often, RPN or DB40X?

RPN ships an update every 4 months, and DB40X every 3 weeks. Most recently, RPN was updated on October 20, 2026 and DB40X 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.*