# i41CX vs Astro PM

The clearest difference is price: Astro PM at Free against i41CX's $7.99. Astro PM also leads on in-app purchases (none vs 4) and update cadence (fortnightly vs every 5 weeks). On ads, device support and iOS requirement there is nothing between them.

Astro PM is free to download; i41CX costs $7.99 up front. i41CX sells 4 one-off in-app purchases. Astro PM asks for nothing beyond the download.

i41CX ships an update every 5 weeks, Astro PM fortnightly. The most recent releases landed on October 17, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | i41CX | Astro PM |
| --- | --- | --- |
| Price | $7.99 | **Free** |
| Rating | **[4.6 (45 ratings)](https://appshunter.io/ios/app/i41cx/id292619450/reviews)** | — |
| Number of ratings | **45** | — |
| Positive reviews | 90.5% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Fortnightly** |
| Monetization | Free with in-app purchases | — |
| Size | 135 MB | 49 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Antonio Lagana](https://appshunter.io/developer/289068868) | [Josh Jones](https://appshunter.io/developer/6804066612) |

## What reviewers say

### i41CX

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

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 |


### Astro PM

[App page](https://appshunter.io/ios/app/astro-pm/id6804066610)

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

**In-app purchases:** none


## Frequently asked questions

### Is i41CX free?

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

### Is Astro PM free?

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

### Do i41CX or Astro PM have ads?

Neither i41CX nor Astro PM shows ads.

### Which is updated more often, i41CX or Astro PM?

i41CX ships an update every 5 weeks, and Astro PM fortnightly. Most recently, i41CX was updated on October 17, 2026 and Astro PM on October 18, 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.*