# Idle Fish Spa vs Krill Keeper

The clearest difference is rating: Krill Keeper at 5.0 against Idle Fish Spa's 4.7. Krill Keeper also leads on update cadence (every 2 weeks vs every 2 months). Idle Fish Spa's advantage is ratings volume (28 vs 9) and iOS requirement (10.0 vs 16.0). On price, ads, in-app purchases and monetization model there is nothing between them.

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

Krill Keeper holds the better App Store score, 5.0 against 4.7. Both are backed by a comparable volume of ratings — 28 and 9 respectively.

Idle Fish Spa ships an update every 2 months, Krill Keeper every 2 weeks. The most recent releases landed on November 3, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | Idle Fish Spa | Krill Keeper |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (28 ratings)](https://appshunter.io/ios/app/idle-fish-spa/id1550262672/reviews) | **[5.0 (9 ratings)](https://appshunter.io/ios/app/krill-keeper/id6759456112/reviews)** |
| Number of ratings | **28** | 9 |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | Yes |
| Update frequency | Every 2 months | **Every 2 weeks** |
| Monetization | Ad-supported | Ad-supported |
| Size | 210 MB | 190 MB |
| Requires iOS | **10.0** | 16.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Yojoy](https://appshunter.io/developer/1472477790) | [Nante Studio](https://appshunter.io/developer/1700809099) |

## What reviewers say

### Idle Fish Spa

[App page](https://appshunter.io/ios/app/idle-fish-spa/id1550262672)

Build and manage your own fish spa empire. Serve customers, discover new fish foods, and upgrade your aquatic inhabitants to earn idle income. Enjoy a relaxing adventure as you expand your business.

**Highlights:** Manage fish spa, Expand fish empire, Discover fish food, Earn idle income, Upgrade fish, Unlock fish

**Features:** macOS Compatibility

**In-app purchases:** none


### Krill Keeper

[App page](https://appshunter.io/ios/app/krill-keeper/id6759456112)

A relaxing aquarium simulation where you nurture a vibrant colony of krill. Feed them, maintain their habitat, and discover unique species to expand your underwater world.

**Highlights:** Raise a krill swarm, Feed and clean tank, Hatch eggs, Collect 36 krill types, Name favorite krill, Play Bubble Pop mini-game, Daily free food

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

**In-app purchases:** none


## Frequently asked questions

### Is Idle Fish Spa free?

Idle Fish Spa is free to download, with no in-app purchases.

### Is Krill Keeper free?

Krill Keeper is free to download, with no in-app purchases.

### Which has better reviews, Idle Fish Spa or Krill Keeper?

Krill Keeper is rated higher. Idle Fish Spa averages 4.7 out of 5 from 28 ratings, while Krill Keeper averages 5.0 from 9 ratings.

### Do Idle Fish Spa or Krill Keeper have ads?

Both Idle Fish Spa and Krill Keeper show ads.

### Which is updated more often, Idle Fish Spa or Krill Keeper?

Idle Fish Spa ships an update every 2 months, and Krill Keeper every 2 weeks. Most recently, Idle Fish Spa was updated on November 3, 2026 and Krill Keeper on November 9, 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.*