# MAR vs CZI Sound

The clearest difference is iOS requirement: MAR at 11.0 against CZI Sound's 13.0. 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.

MAR ships an update every 9 months, CZI Sound every 8 months. The most recent releases landed on November 11, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | MAR | CZI Sound |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 9 months | **Every 8 months** |
| Size | 15 MB | 64 MB |
| Requires iOS | **11.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [European Maritime Safety Agency](https://appshunter.io/developer/1057632331) | [Guangzhou Chengzhi Intelligent Machine Technology Co., Ltd.](https://appshunter.io/developer/1675437495) |

## What reviewers say

### MAR

[App page](https://appshunter.io/ios/app/mar-cis/id1234942090)

**Features:** macOS Compatibility

**In-app purchases:** none


### CZI Sound

[App page](https://appshunter.io/ios/app/czi-sound/id6446013579)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is MAR free?

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

### Is CZI Sound free?

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

### Do MAR or CZI Sound have ads?

Neither MAR nor CZI Sound shows ads.

### Which is updated more often, MAR or CZI Sound?

MAR ships an update every 9 months, and CZI Sound every 8 months. Most recently, MAR was updated on November 11, 2026 and CZI Sound on November 3, 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.*