# π Challenge vs Pi Recall 100

The clearest difference is in-app purchases: π Challenge at none against Pi Recall 100's 1. π Challenge also leads on device support (3 vs 1) and iOS requirement (13.0 vs 16.4). On price and ads there is nothing between them.

Both are free to download. Pi Recall 100 sells 1 one-off in-app purchase. π Challenge asks for nothing beyond the download.

## The numbers

| Metric | π Challenge | Pi Recall 100 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 9 months | — |
| Size | 29 MB | 52 MB |
| Requires iOS | **13.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Warashibe Tech LLC](https://appshunter.io/developer/1567747524) | [MITSURU ADACHI](https://appshunter.io/developer/6794788162) |

## What reviewers say

### π Challenge

[App page](https://appshunter.io/ios/app/challenge/id6743357759)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Pi Recall 100

[App page](https://appshunter.io/ios/app/pi-recall-100/id6796900142)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 100-Digit Challenge Premium | $2.99 | one-time |


## Frequently asked questions

### Is π Challenge free?

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

### Is Pi Recall 100 free?

Pi Recall 100 is free to download, with in-app purchases available.

### Do π Challenge or Pi Recall 100 have ads?

Neither π Challenge nor Pi Recall 100 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.*