# Why? 과학 vs Lumi Math Planet

The clearest difference is update cadence: Lumi Math Planet at every 3 days against Why? 과학's monthly. Lumi Math Planet also leads on device support (3 vs 1). Why? 과학's advantage is iOS requirement (6.0 vs 15.1). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Why? 과학 sells 11 one-off in-app purchases and Lumi Math Planet sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Why? 과학 ships an update monthly, Lumi Math Planet every 3 days. The most recent releases landed on September 27, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Why? 과학 | Lumi Math Planet |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (1 ratings)](https://appshunter.io/ios/app/why/id433116895/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 days** |
| Monetization | Free | — |
| Size | 15 MB | 56 MB |
| Requires iOS | **6.0** | 15.1 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [(주)예림당](https://appshunter.io/developer/565049166) | [Guan Feng Lai](https://appshunter.io/developer/1136144960) |

## 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 |


### Lumi Math Planet

[App page](https://appshunter.io/ios/app/lumi-math-planet-explorer/id6778269699)

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock the Full Galaxy | $4.99 | one-time |


## Frequently asked questions

### Is Why? 과학 free?

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

### Is Lumi Math Planet free?

Lumi Math Planet is free to download, with in-app purchases available.

### Do Why? 과학 or Lumi Math Planet have ads?

Neither Why? 과학 nor Lumi Math Planet shows ads.

### Which is updated more often, Why? 과학 or Lumi Math Planet?

Why? 과학 ships an update monthly, and Lumi Math Planet every 3 days. Most recently, Why? 과학 was updated on September 27, 2026 and Lumi Math Planet on October 14, 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.*