# Miracle Mind  奇蹟心靈 vs Challenge21

The clearest difference is device support: Miracle Mind  奇蹟心靈 at 3 against Challenge21's —. On price, in-app purchases and iOS requirement 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 | Miracle Mind  奇蹟心靈 | Challenge21 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | — |
| Update frequency | Fortnightly | — |
| Size | 35 MB | 31 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | **iPhone, iPad, iPod** | — |
| Age rating | 4+ | 4+ |
| Developer | [Yu Tse Lin](https://appshunter.io/developer/1821210767) | [Astra Zenith Ltd.](https://appshunter.io/developer/1834145226) |

## What reviewers say

### Miracle Mind  奇蹟心靈

[App page](https://appshunter.io/ios/app/miracle-mind/id6757657382)

**Features:** macOS Compatibility

**In-app purchases:** none


### Challenge21

[App page](https://appshunter.io/ios/app/challenge21/id6759655419)

**In-app purchases:** none


## Frequently asked questions

### Is Miracle Mind  奇蹟心靈 free?

Miracle Mind  奇蹟心靈 is free to download, with no in-app purchases.

### Is Challenge21 free?

Challenge21 is free to download, with no in-app purchases.

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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.*