# Primality vs Prime Factors +Calc

The clearest difference is update cadence: Prime Factors +Calc at weekly against Primality's every 2 months. Primality's advantage is iOS requirement (13.2 vs 16.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Primality ships an update every 2 months, Prime Factors +Calc weekly. Both last shipped on October 24, 2026.

## The numbers

| Metric | Primality | Prime Factors +Calc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (26 ratings)](https://appshunter.io/ios/app/primality/id1516003672/reviews)** | — |
| Number of ratings | **26** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Weekly** |
| Monetization | Free | — |
| Size | 1 MB | 1 MB |
| Requires iOS | **13.2** | 16.0 |
| Devices | iPhone, iPod | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Bruce Schechter](https://appshunter.io/developer/1515359087) | [Kazuaki Oshiba](https://appshunter.io/developer/1813699478) |

## What reviewers say

### Primality

[App page](https://appshunter.io/ios/app/primality/id1516003672)

This app determines if a given integer is prime or provides its prime factors. It also calculates the ordinal position of prime numbers found, up to a certain limit.

**Highlights:** Primality testing, Prime factorization, Prime ordinality calculation, Large integer support (up to 999,999,999,999), Clean and simple interface

**Features:** macOS Compatibility

**In-app purchases:** none


### Prime Factors +Calc

[App page](https://appshunter.io/ios/app/prime-factors-plus-calc/id6745752731)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Primality free?

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

### Is Prime Factors +Calc free?

Prime Factors +Calc is free to download, with no in-app purchases.

### Do Primality or Prime Factors +Calc have ads?

Neither Primality nor Prime Factors +Calc shows ads.

### Which is updated more often, Primality or Prime Factors +Calc?

Primality ships an update every 2 months, and Prime Factors +Calc weekly. Most recently, Primality was updated on October 24, 2026 and Prime Factors +Calc on October 24, 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.*