# RLM vs DB40X

The clearest difference is in-app purchases: DB40X at none against RLM's 4. DB40X also leads on review sentiment (78% vs 53%) and ratings volume (7 vs 1). RLM's advantage is rating (5.0 vs 4.7). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. RLM sells 4 in-app purchases, starting at $0.49 per month. DB40X asks for nothing beyond the download.

RLM holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: DB40X has 7 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 53% of RLM's written reviews are positive against 78% of DB40X's, so the app with the better star average is not the one people write more warmly about.

RLM ships an update monthly, DB40X every 3 weeks. The most recent releases landed on November 3, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | RLM | DB40X |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/rlm-17bx-calculator/id1593889938/reviews)** | [4.7 (7 ratings)](https://appshunter.io/ios/app/db40x/id6624315901/reviews) |
| Number of ratings | 1 | **7** |
| Positive reviews | 53.3% of reviews | **77.8% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 weeks** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 7 MB | 7 MB |
| Requires iOS | 26.0 | **14.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [R.L.M. Software](https://appshunter.io/developer/289639238) | [Christophe de Dinechin](https://appshunter.io/developer/1761608161) |

## What reviewers say

### RLM

[App page](https://appshunter.io/ios/app/rlm-17bx-calculator/id1593889938)

This app offers a comprehensive suite of calculators for finance, business, science, and general use. It includes specialized worksheets for loans, investments, statistics, and complex mathematical functions, designed to leverage iOS device capabilities.

**Highlights:** Finance worksheets (amortization, bond pricing, options), Business calculations (bill split, break-even, currency), Statistical analysis (probability, regressions), Scientific functions (complex numbers, vectors), Unit and currency conversions, Equation solver, Date and time calculations

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Virtual Battery | $0.49 | per month |
| Semi-Annual Subscription | $2.99 | per 6 months |
| Annual Subscription | $5.99 | per year |
| Lifetime Purchase | $9.99 | one-time |


### 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, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is RLM free?

RLM is free to download, with in-app purchases available.

### Is DB40X free?

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

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

RLM is rated higher. RLM averages 5.0 out of 5 from 1 ratings, while DB40X averages 4.7 from 7 ratings.

### Do RLM or DB40X have ads?

Neither RLM nor DB40X shows ads.

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

RLM ships an update monthly, and DB40X every 3 weeks. Most recently, RLM was updated on November 3, 2026 and DB40X on November 4, 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.*