# Why? 과학 vs 재밌는천자문

The clearest difference is in-app purchases: 재밌는천자문 at none against Why? 과학's 11. 재밌는천자문 also leads on update cadence (every 10 days vs monthly). Why? 과학's advantage is ads (none vs shown) and iOS requirement (6.0 vs 17.0). On price and device support there is nothing between them.

Both are free to download. Why? 과학 sells 11 one-off in-app purchases. 재밌는천자문 asks for nothing beyond the download.

Why? 과학 ships an update monthly, 재밌는천자문 every 10 days. The most recent releases landed on October 20, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | Why? 과학 | 재밌는천자문 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (1 ratings)](https://appshunter.io/ios/app/why/id433116895/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 21.6% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Monthly | **Every 10 days** |
| Monetization | Free | — |
| Size | 15 MB | 33 MB |
| Requires iOS | **6.0** | 17.0 |
| Devices | iPad | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [(주)예림당](https://appshunter.io/developer/565049166) | [Kiyong Kim](https://appshunter.io/developer/1216526596) |

## What reviewers say

### Why? 과학

[App page](https://appshunter.io/ios/app/why/id433116895)

This app makes complex science topics easy and fun for children through engaging comics and vivid illustrations. It aligns with elementary school science curricula, making it a great study aid. Continuous content updates ensure an ever-growing library of scientific exploration.

**Highlights:** Engaging comic format, Vivid illustrations and real photos, Curriculum-aligned content, Expert-reviewed science information, Continuous content updates, International export success

**Features:** macOS Compatibility

**In-app purchases (11)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Why 우주 | $5.99 | one-time |
| Why 인체 | $5.99 | one-time |
| Why 바다 | $5.99 | one-time |
| Why 곤충 | $5.99 | one-time |
| Why 사춘기와 성 | $5.99 | one-time |
| Why 공룡 | $5.99 | one-time |
| Why 똥 | $5.99 | one-time |
| Why 외계인과 UFO | $5.99 | one-time |
| Why 독있는 동식물 | $5.99 | one-time |
| Why 응급처치 | $5.99 | one-time |
| Why 전기전자 | $5.99 | one-time |


### 재밌는천자문

[App page](https://appshunter.io/ios/app/id6761768317)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Why? 과학 free?

Why? 과학 is free to download, with in-app purchases available.

### Is 재밌는천자문 free?

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

### Do Why? 과학 or 재밌는천자문 have ads?

재밌는천자문 shows ads; Why? 과학 does not.

### Which is updated more often, Why? 과학 or 재밌는천자문?

Why? 과학 ships an update monthly, and 재밌는천자문 every 10 days. Most recently, Why? 과학 was updated on October 20, 2026 and 재밌는천자문 on October 4, 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.*