# Calx vs Formula Calculator #

The clearest difference is price: Formula Calculator # at Free against Calx's $0.99. Formula Calculator # also leads on update cadence (every 5 weeks vs every 24 months). Calx's advantage is in-app purchases (none vs 4) and ads (none vs shown). On rating, review sentiment, ratings volume and device support there is nothing between them.

Formula Calculator # is free to download; Calx costs $0.99 up front. Formula Calculator # sells 4 one-off in-app purchases. Calx asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for Calx against 5.0 for Formula Calculator #. Both are backed by a comparable volume of ratings — 2 and 2 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

Calx ships an update every 24 months, Formula Calculator # every 5 weeks. The most recent releases landed on August 12, 2026 and September 14, 2026 respectively.

## The numbers

| Metric | Calx | Formula Calculator # |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [5.0 (2 ratings)](https://appshunter.io/ios/app/calx-stack-calculator/id928929230/reviews) | [5.0 (2 ratings)](https://appshunter.io/ios/app/formula-calculator/id6504839903/reviews) |
| Number of ratings | 2 | 2 |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 24 months | **Every 5 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 4 MB | 67 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Daniel Clelland](https://appshunter.io/developer/912177584) | [威 刘](https://appshunter.io/developer/1465235012) |

## What reviewers say

### Calx

[App page](https://appshunter.io/ios/app/calx-stack-calculator/id928929230)

This calculator app utilizes Reverse Polish Notation (RPN) for efficient calculations by manipulating numbers on a stack. It offers a guided tutorial, gestural interaction, multiple keypads with various functions, and customization options for fonts and colors.

**Highlights:** Reverse Polish Notation (RPN), Gestural interaction, Multiple keypads (basic, scientific, statistical), Customizable fonts and colors, Guided tutorial

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

**In-app purchases:** none


### Formula Calculator #

[App page](https://appshunter.io/ios/app/formula-calculator/id6504839903)

Perform calculations with a vast library of built-in formulas or create your own. Save and sync custom formulas to the cloud for easy access across devices. Includes a comprehensive scientific calculator.

**Highlights:** Extensive built-in calculation formulas, Create and save custom formulas, Cloud synchronization for custom formulas, Share custom formulas with others, Comprehensive scientific calculator

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 month subscription | $1.49 | one-time |
| 3 months subscription | $2.49 | one-time |
| 6 months subscription | $3.49 | one-time |
| 1 year subscription | $4.49 | one-time |


## Frequently asked questions

### Is Calx free?

Calx costs $0.99, with no in-app purchases.

### Is Formula Calculator # free?

Formula Calculator # is free to download, with in-app purchases available.

### Which has better reviews, Calx or Formula Calculator #?

Calx and Formula Calculator # are both rated 5.0 out of 5 on the App Store, from 2 and 2 ratings respectively.

### Do Calx or Formula Calculator # have ads?

Formula Calculator # shows ads; Calx does not.

### Which is updated more often, Calx or Formula Calculator #?

Calx ships an update every 24 months, and Formula Calculator # every 5 weeks. Most recently, Calx was updated on August 12, 2026 and Formula Calculator # on September 14, 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.*