# RPN vs DB40X

The clearest difference is price: DB40X at Free against RPN's $1.99. DB40X also leads on update cadence (every 3 weeks vs every 6 months) and rating (4.7 vs 4.4). RPN's advantage is chart position (#185 vs unranked) and iOS requirement (12.0 vs 14.0). On review sentiment, ratings volume, ads and in-app purchases 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 4.4. Both are backed by a comparable volume of ratings — 14 and 7 respectively. Written reviews complicate that: 71% 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 6 months, DB40X every 3 weeks. The most recent releases landed on October 20, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | RPN | DB40X |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [4.4 (14 ratings)](https://appshunter.io/ios/app/rpn-35-sd/id956224485/reviews) | **[4.7 (7 ratings)](https://appshunter.io/ios/app/db40x/id6624315901/reviews)** |
| Number of ratings | **14** | 7 |
| Positive reviews | **71.4% of reviews** | 66.7% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 3 weeks** |
| Monetization | Paid | **Free** |
| Best chart rank | **#185** | — |
| 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-35-sd/id956224485)

**Currently charting:** #185 Top Paid · Productivity (US App Store)

This app emulates the first pocket scientific calculator, offering a photo-realistic vintage experience. It simulates original operating speeds and unique arithmetic bugs, with optional modern enhancements like non-volatile registers.

**Highlights:** Photo-realistic look-and-feel, Multiple vintage skins, Vintage and Enhanced modes, Optional key-click and key-glow, Swipe to correct input, Display stack and memory registers

**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 4.4 out of 5 from 14 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 6 months, and DB40X every 3 weeks. Most recently, RPN was updated on October 20, 2026 and DB40X on October 3, 2026.

---

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