# Formula Calculator Alpha vs Rondo

The clearest difference is in-app purchases: Formula Calculator Alpha at none against Rondo's 5. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Rondo sells 5 one-off in-app purchases. Formula Calculator Alpha asks for nothing beyond the download.

Formula Calculator Alpha ships an update every 9 days, Rondo every 4 days. The most recent releases landed on September 25, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | Formula Calculator Alpha | Rondo |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/rondo-prime-factorization/id6784029039/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 9 days | **Every 4 days** |
| Monetization | — | Free with in-app purchases |
| Size | 3 MB | 8 MB |
| Requires iOS | 26.2 | **26.0** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [子宸 魏](https://appshunter.io/developer/1890054508) | [KEN TOMINAGA](https://appshunter.io/developer/975026926) |

## What reviewers say

### Formula Calculator Alpha

[App page](https://appshunter.io/ios/app/formula-calculator-alpha/id6775855674)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


### Rondo

[App page](https://appshunter.io/ios/app/rondo-prime-factorization/id6784029039)

Explore the mathematical beauty of numbers through interactive, animated factorization diagrams. Watch numbers dance, hear their unique songs, and even visualize them in augmented reality. Discover the stories behind special numbers and personalize your experience with customizable palettes and sounds.

**Highlights:** Animated factorization diagrams, Augmented reality number visualization, Auditory representation of factors, Interactive number exploration, Field Guide for special numbers, Home screen and Apple Watch widgets, Customizable color palettes and sounds

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tip a prime · 199 | $1.99 | one-time |
| Tip a prime · 499 | $4.99 | one-time |
| Rondo Pro | $4.99 | one-time |
| Tip a prime · 599 | $5.99 | one-time |
| Tip a prime · 1999 | $19.99 | one-time |


## Frequently asked questions

### Is Formula Calculator Alpha free?

Formula Calculator Alpha is free to download, with no in-app purchases.

### Is Rondo free?

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

### Do Formula Calculator Alpha or Rondo have ads?

Neither Formula Calculator Alpha nor Rondo shows ads.

### Which is updated more often, Formula Calculator Alpha or Rondo?

Formula Calculator Alpha ships an update every 9 days, and Rondo every 4 days. Most recently, Formula Calculator Alpha was updated on September 25, 2026 and Rondo on October 1, 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.*