# i41CX vs RPN

The clearest difference is in-app purchases: RPN at none against i41CX's 4. RPN also leads on price ($1.99 vs $7.99) and iOS requirement (12.0 vs 16.0). i41CX's advantage is update cadence (weekly vs every 6 months) and rating (4.6 vs 4.4). On ads and device support there is nothing between them.

i41CX costs $7.99 and RPN $1.99 up front. i41CX sells 4 one-off in-app purchases. RPN asks for nothing beyond the download.

i41CX holds the better App Store score, 4.6 against 4.4. Both are backed by a comparable volume of ratings — 45 and 14 respectively. Written reviews point the same way: 90% of i41CX's written reviews are positive against 71% of RPN's.

i41CX ships an update weekly, RPN every 6 months. The most recent releases landed on October 26, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | i41CX | RPN |
| --- | --- | --- |
| Price | $7.99 | **$1.99** |
| Rating | **[4.6 (45 ratings)](https://appshunter.io/ios/app/i41cx/id292619450/reviews)** | [4.4 (14 ratings)](https://appshunter.io/ios/app/rpn-35-sd/id956224485/reviews) |
| Number of ratings | **45** | 14 |
| Positive reviews | **90.5% of reviews** | 71.4% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Weekly** | Every 6 months |
| Monetization | **Free with in-app purchases** | Paid |
| Best chart rank | **#197** | — |
| Size | 135 MB | 14 MB |
| Requires iOS | 16.0 | **12.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Antonio Lagana](https://appshunter.io/developer/289068868) | [CuVee Software](https://appshunter.io/developer/424873503) |

## What reviewers say

### i41CX

[App page](https://appshunter.io/ios/app/i41cx/id292619450)

**Currently charting:** #197 Top Paid · Productivity (US App Store)

This app offers a powerful RPN scientific calculator experience, functionally equivalent to a renowned model. It provides extensive memory registers, over 300 built-in functions, and programmability. Advanced features can be unlocked via in-app purchases.

**Highlights:** RPN logic with 4-element stack, 319 main and 124 extended memory registers, Over 300 built-in functions, Programmable up to 2000 lines, User-definable keyboard, Bluetooth keyboard support, Device integration features

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Overlays Upgrade | $2.99 | one-time |
| Printer Upgrade | $3.99 | one-time |
| CAS Upgrade | $7.99 | one-time |
| i41CX+ Features Upgrade | $17.99 | one-time |


### RPN

[App page](https://appshunter.io/ios/app/rpn-35-sd/id956224485)

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


## Frequently asked questions

### Is i41CX free?

i41CX costs $7.99, and also offers in-app purchases.

### Is RPN free?

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

### Which has better reviews, i41CX or RPN?

i41CX is rated higher. i41CX averages 4.6 out of 5 from 45 ratings, while RPN averages 4.4 from 14 ratings.

### Do i41CX or RPN have ads?

Neither i41CX nor RPN shows ads.

### Which is updated more often, i41CX or RPN?

i41CX ships an update weekly, and RPN every 6 months. Most recently, i41CX was updated on October 26, 2026 and RPN on October 28, 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.*