# The Marimo vs Jellyfish Simulator

The Marimo and Jellyfish Simulator both sit at 4.4 stars, but that hides the real split: 80% of The Marimo's written reviews are positive against 50% of Jellyfish Simulator's. Jellyfish Simulator's advantage is device support (4 vs 2) and iOS requirement (12.0 vs 15.6). On price, rating, ratings volume and update cadence there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 4.4 for The Marimo against 4.5 for Jellyfish Simulator. Both are backed by a comparable volume of ratings — 16 and 6 respectively. Written reviews are what separate them: 80% of The Marimo's written reviews are positive against 50% of Jellyfish Simulator's.

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 16, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | The Marimo | Jellyfish Simulator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.4 (16 ratings)](https://appshunter.io/ios/app/the-marimo/id398361669/reviews) | **[4.5 (6 ratings)](https://appshunter.io/ios/app/jellyfish-simulator/id980837740/reviews)** |
| Number of ratings | **16** | 6 |
| Positive reviews | **79.6% of reviews** | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | Yes |
| Update frequency | Every 3 months | Every 3 months |
| Monetization | Ad-supported | Ad-supported |
| Size | 18 MB | 14 MB |
| Requires iOS | 15.6 | **12.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Kosuke Ogawa](https://appshunter.io/developer/379825481) | [KENSHI DOI](https://appshunter.io/developer/709264908) |

## What reviewers say

### The Marimo

[App page](https://appshunter.io/ios/app/the-marimo/id398361669)

Care for a virtual green ball creature that grows over time. Keep its environment clean and provide light to ensure its survival. Customize its appearance and interact with it through various gestures.

**Highlights:** Virtual pet care, Growth simulation, Environment maintenance, Customization options, Interactive controls, Social sharing

**Features:** Vision Pro support

**In-app purchases:** none


### Jellyfish Simulator

[App page](https://appshunter.io/ios/app/jellyfish-simulator/id980837740)

Care for virtual jellyfish by cleaning their tank and circulating water. New jellyfish will appear and grow, with six types available. Play data is automatically saved to iCloud and accessible on other devices, including Apple Watch.

**Highlights:** Jellyfish growth simulation, Tank cleaning mechanics, Multiple jellyfish types, iCloud data saving, Apple Watch companion app, AR/VR 3D viewing

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is The Marimo free?

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

### Is Jellyfish Simulator free?

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

### Which has better reviews, The Marimo or Jellyfish Simulator?

Jellyfish Simulator is rated higher. The Marimo averages 4.4 out of 5 from 16 ratings, while Jellyfish Simulator averages 4.5 from 6 ratings.

### Do The Marimo or Jellyfish Simulator have ads?

Both The Marimo and Jellyfish Simulator show ads.

### Which is updated more often, The Marimo or Jellyfish Simulator?

The Marimo ships an update every 3 months, and Jellyfish Simulator every 3 months. Most recently, The Marimo was updated on October 16, 2026 and Jellyfish Simulator on October 5, 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.*