# 河马英文阅读器 (Hippo Reader) vs 四维世界：空间探索

The clearest difference is price: 四维世界：空间探索 at Free against 河马英文阅读器 (Hippo Reader)'s $0.99. 四维世界：空间探索 also leads on ads (none vs shown) and update cadence (every 5 days vs every 6 weeks). 河马英文阅读器 (Hippo Reader)'s advantage is ratings volume (41 vs 1) and iOS requirement (13.0 vs 16.0). On in-app purchases and device support there is nothing between them.

四维世界：空间探索 is free to download; 河马英文阅读器 (Hippo Reader) costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

四维世界：空间探索 holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: 河马英文阅读器 (Hippo Reader) has 41 ratings behind it against 1, so its average is the more settled of the two.

河马英文阅读器 (Hippo Reader) ships an update every 6 weeks, 四维世界：空间探索 every 5 days. The most recent releases landed on October 16, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | 河马英文阅读器 (Hippo Reader) | 四维世界：空间探索 |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [4.8 (41 ratings)](https://appshunter.io/ios/app/hippo-reader/id1579211407/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/id6787638663/reviews)** |
| Number of ratings | **41** | 1 |
| Positive reviews | 94.3% of reviews | — |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 6 weeks | **Every 5 days** |
| Monetization | Paid | — |
| Size | 57 MB | 4 MB |
| Requires iOS | **13.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [LexyTech Ltd.](https://appshunter.io/developer/1643712954) | [越 王](https://appshunter.io/developer/6787476168) |

## What reviewers say

### 河马英文阅读器 (Hippo Reader)

[App page](https://appshunter.io/ios/app/hippo-reader/id1579211407)

This app offers a minimalist English e-book reader for an immersive reading experience. It allows users to easily look up word meanings, translate sentences, and access various dictionary definitions with a simple tap or double-tap. Features include offline reading, customizable fonts, and note-taking capabilities.

**Highlights:** Integrated dictionary and translation, Offline reading support, Customizable fonts and reading styles, Note-taking and export, Vocabulary analysis by level, Web page reading with word lookup

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

**In-app purchases:** none


### 四维世界：空间探索

[App page](https://appshunter.io/ios/app/id6787638663)

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

**In-app purchases:** none


## Frequently asked questions

### Is 河马英文阅读器 (Hippo Reader) free?

河马英文阅读器 (Hippo Reader) costs $0.99, with no in-app purchases.

### Is 四维世界：空间探索 free?

四维世界：空间探索 is free to download, with no in-app purchases.

### Which has better reviews, 河马英文阅读器 (Hippo Reader) or 四维世界：空间探索?

四维世界：空间探索 is rated higher. 河马英文阅读器 (Hippo Reader) averages 4.8 out of 5 from 41 ratings, while 四维世界：空间探索 averages 5.0 from 1 ratings.

### Do 河马英文阅读器 (Hippo Reader) or 四维世界：空间探索 have ads?

河马英文阅读器 (Hippo Reader) shows ads; 四维世界：空间探索 does not.

### Which is updated more often, 河马英文阅读器 (Hippo Reader) or 四维世界：空间探索?

河马英文阅读器 (Hippo Reader) ships an update every 6 weeks, and 四维世界：空间探索 every 5 days. Most recently, 河马英文阅读器 (Hippo Reader) was updated on October 16, 2026 and 四维世界：空间探索 on October 12, 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.*