# x vs permutation group

The clearest difference is iOS requirement: permutation group at 16.6 against x's 18.0. 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.

## The numbers

| Metric | x | permutation group |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Fortnightly | — |
| Size | 1 MB | 6 MB |
| Requires iOS | 18.0 | **16.6** |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [FMILLET](https://appshunter.io/developer/550887984) | [Sungjun Kim](https://appshunter.io/developer/1602461985) |

## What reviewers say

### x

[App page](https://appshunter.io/ios/app/x-cal-plus/id6747112339)

**Features:** macOS Compatibility

**In-app purchases:** none


### permutation group

[App page](https://appshunter.io/ios/app/permutation-group/id6757737753)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is x free?

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

### Is permutation group free?

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

### Do x or permutation group have ads?

Neither x nor permutation group shows ads.

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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.*