# 퍼스텝 vs 자연과학OX

The clearest difference is update cadence: 퍼스텝 at every 8 days against 자연과학OX's every 4 months. 퍼스텝 also leads on iOS requirement (11.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. 퍼스텝 sells 10 in-app purchases, starting at $3.99 per month and 자연과학OX sells 3 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

퍼스텝 ships an update every 8 days, 자연과학OX every 4 months. The most recent releases landed on September 23, 2026 and August 25, 2026 respectively.

## The numbers

| Metric | 퍼스텝 | 자연과학OX |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 8 days** | Every 4 months |
| Monetization | — | Freemium |
| Size | 31 MB | 26 MB |
| Requires iOS | **11.0** | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [FIRSTEP COMPANY CO.,LTD](https://appshunter.io/developer/1483910762) | [CHAE HYUCK LEE](https://appshunter.io/developer/1658701307) |

## What reviewers say

### 퍼스텝

[App page](https://appshunter.io/ios/app/id6444601083)

**Features:** macOS Compatibility

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 프리미엄 멤버십 | $3.99 | per month |
| 프리미엄 멤버십 - 무료체험포함 | $3.99 | per month |
| 멤버십  그룹 챌린지 이용권 | $0.99 | one-time |
| 멤버십  그룹 챌린지 이용권 | $2.99 | one-time |
| 멤버십  그룹 챌린지 이용권 | $6.99 | one-time |
| 일반  그룹 챌린지 이용권 | $12.99 | one-time |
| 멤버십  그룹 챌린지 이용권 | $15.99 | one-time |
| 일반  그룹 챌린지 이용권 | $32.99 | one-time |
| 멤버십  그룹 챌린지 이용권 | $32.99 | one-time |
| 일반  그룹 챌린지 이용권 | $69.99 | one-time |


### 자연과학OX

[App page](https://appshunter.io/ios/app/ox/id6479007396)

This app offers practice quizzes for recent natural science topics, covering physics, chemistry, biology, and earth science. It provides subscription options for enhanced learning features and detailed explanations.

**Highlights:** Physics quizzes, Chemistry quizzes, Biology quizzes, Earth science quizzes, Subscription for explanations, Practice quizzes

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 단원 설정권 | $2.99 | per month |
| 무제한 해설권 | $3.99 | per month |
| 평생 자유 이용권 | $19.99 | one-time |


## Frequently asked questions

### Is 퍼스텝 free?

퍼스텝 is free to download, with in-app purchases available.

### Is 자연과학OX free?

자연과학OX is free to download, with in-app purchases available.

### Do 퍼스텝 or 자연과학OX have ads?

Neither 퍼스텝 nor 자연과학OX shows ads.

### Which is updated more often, 퍼스텝 or 자연과학OX?

퍼스텝 ships an update every 8 days, and 자연과학OX every 4 months. Most recently, 퍼스텝 was updated on September 23, 2026 and 자연과학OX on August 25, 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.*