# RPN Memory Calculator vs x

The clearest difference is in-app purchases: x at none against RPN Memory Calculator's 1. x also leads on update cadence (fortnightly vs every 4 months). RPN Memory Calculator's advantage is device support (3 vs 1) and iOS requirement (11.3 vs 18.0). On price and ads there is nothing between them.

Both are free to download. RPN Memory Calculator sells 1 one-off in-app purchase. x asks for nothing beyond the download.

RPN Memory Calculator ships an update every 4 months, x fortnightly. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | RPN Memory Calculator | x |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 months | **Fortnightly** |
| Monetization | Free | — |
| Size | 8 MB | 1 MB |
| Requires iOS | **11.3** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Neverest Limited](https://appshunter.io/developer/1360645388) | [FMILLET](https://appshunter.io/developer/550887984) |

## What reviewers say

### RPN Memory Calculator

[App page](https://appshunter.io/ios/app/rpn-memory-calculator/id1398878075)

This application provides a straightforward reverse Polish notation (RPN) calculator with essential functions and memory operations. It also includes integrated unit conversions for various measurements, allowing for quick conversions directly within the app. The calculator remembers your session, preserving all registers and memory values for future use.

**Highlights:** Reverse Polish Notation (RPN) input, Seven core calculator functions, Memory operations, Integrated unit conversions (Speed, Mass, Temperature, Pressure), Persistent state saving, Three visible registers

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Calculator Unit Conversions | $0.99 | one-time |


### x

[App page](https://appshunter.io/ios/app/x-cal-plus/id6747112339)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is RPN Memory Calculator free?

RPN Memory Calculator is free to download, with in-app purchases available.

### Is x free?

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

### Do RPN Memory Calculator or x have ads?

Neither RPN Memory Calculator nor x shows ads.

### Which is updated more often, RPN Memory Calculator or x?

RPN Memory Calculator ships an update every 4 months, and x fortnightly. Most recently, RPN Memory Calculator was updated on October 24, 2026 and x on October 25, 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.*