# Is it Prime? vs Just A Calc

The clearest difference is iOS requirement: Just A Calc at 12.0 against Is it Prime?'s 15.0. On price, update cadence, ads and in-app purchases there is nothing between them.

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

Is it Prime? ships an update every 74 months, Just A Calc every 38 months. The most recent releases landed on October 31, 2026 and November 2, 2026 respectively.

## The numbers

| Metric | Is it Prime? | Just A Calc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.2 (5 ratings)](https://appshunter.io/ios/app/is-it-prime/id326095651/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 71.4% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 74 months | **Every 38 months** |
| Monetization | Free | — |
| Size | 1 MB | 10 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Wismar](https://appshunter.io/developer/307757950) | [Tom Doherty](https://appshunter.io/developer/1112286724) |

## What reviewers say

### Is it Prime?

[App page](https://appshunter.io/ios/app/is-it-prime/id326095651)

Enter any number to instantly determine if it is a prime number or not. This straightforward utility provides a quick answer to your mathematical curiosity.

**Highlights:** Prime number identification, Simple number input, Instant yes/no results

**Features:** macOS Compatibility

**In-app purchases:** none


### Just A Calc

[App page](https://appshunter.io/ios/app/just-a-calc/id1112349564)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Is it Prime? free?

Is it Prime? is free to download, with no in-app purchases.

### Is Just A Calc free?

Just A Calc is free to download, with no in-app purchases.

### Do Is it Prime? or Just A Calc have ads?

Neither Is it Prime? nor Just A Calc shows ads.

### Which is updated more often, Is it Prime? or Just A Calc?

Is it Prime? ships an update every 74 months, and Just A Calc every 38 months. Most recently, Is it Prime? was updated on October 31, 2026 and Just A Calc on November 2, 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.*