# 宇宙の英単語 vs CosmicObserver

The clearest difference is in-app purchases: 宇宙の英単語 at none against CosmicObserver's 1. 宇宙の英単語 also leads on update cadence (fortnightly vs every 5 weeks). CosmicObserver's advantage is iOS requirement (18.0 vs 26.0). On price, ads and device support there is nothing between them.

Both are free to download. CosmicObserver sells 1 one-off in-app purchase. 宇宙の英単語 asks for nothing beyond the download.

宇宙の英単語 ships an update fortnightly, CosmicObserver every 5 weeks. The most recent releases landed on September 10, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | 宇宙の英単語 | CosmicObserver |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 5 weeks |
| Size | 21 MB | 188 MB |
| Requires iOS | 26.0 | **18.0** |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 17+ | 4+ |
| Developer | [Hiroaki Toya](https://appshunter.io/developer/1515661642) | [Yuichi Okuno](https://appshunter.io/developer/1803911141) |

## What reviewers say

### 宇宙の英単語

[App page](https://appshunter.io/ios/app/id6783165808)

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

**In-app purchases:** none


### CosmicObserver

[App page](https://appshunter.io/ios/app/cosmicobserver/id6787430312)

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Cosmic Pass | $4.99 | one-time |


## Frequently asked questions

### Is 宇宙の英単語 free?

宇宙の英単語 is free to download, with no in-app purchases.

### Is CosmicObserver free?

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

### Do 宇宙の英単語 or CosmicObserver have ads?

Neither 宇宙の英単語 nor CosmicObserver shows ads.

### Which is updated more often, 宇宙の英単語 or CosmicObserver?

宇宙の英単語 ships an update fortnightly, and CosmicObserver every 5 weeks. Most recently, 宇宙の英単語 was updated on September 10, 2026 and CosmicObserver on October 24, 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.*