# Red Koto vs Koto Sim

The clearest difference is price: Koto Sim at Free against Red Koto's $8.99. Koto Sim also leads on rating (5.0 vs 1.0) and update cadence (every 4 weeks vs every 6 months). Red Koto's advantage is in-app purchases (none vs 1) and ads (none vs shown). On device support and iOS requirement there is nothing between them.

Koto Sim is free to download; Red Koto costs $8.99 up front. Koto Sim sells 1 one-off in-app purchase. Red Koto asks for nothing beyond the download.

Koto Sim holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 1 and 4 respectively.

Red Koto ships an update every 6 months, Koto Sim every 4 weeks. The most recent releases landed on October 1, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Red Koto | Koto Sim |
| --- | --- | --- |
| Price | $8.99 | **Free** |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/red-koto/id387575031/reviews) | **[5.0 (4 ratings)](https://appshunter.io/ios/app/koto-sim/id6740201723/reviews)** |
| Number of ratings | 1 | **4** |
| Positive reviews | 40.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 6 months | **Every 4 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 29 MB | 125 MB |
| Requires iOS | 13.0 | **12.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Oliver Grimm](https://appshunter.io/developer/380669289) | [Alper Kahriman](https://appshunter.io/developer/1054578352) |

## What reviewers say

### Red Koto

[App page](https://appshunter.io/ios/app/red-koto/id387575031)

Explore a collection of 74 Koto tunings by a renowned virtuoso. Use it to tune your instrument by ear, study scales, or play along with unique compositions. The app features interactive strings and notes for an immersive musical experience.

**Highlights:** 74 Koto tunings, Tuning by ear, Scale study, Interactive string display, Plucked and picked sounds, Customizable tuning order

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

**In-app purchases:** none


### Koto Sim

[App page](https://appshunter.io/ios/app/koto-sim/id6740201723)

Experience the authentic sound and feel of Japan's national string instrument. This app offers realistic koto tones, customizable interfaces, and multiple play modes for musicians and enthusiasts. Record and share your creations within an immersive simulation.

**Highlights:** Authentic koto sounds, Customizable interface and tuning, Three dynamic play modes, Built-in recorder, Screen recording for sharing, Immersive simulation environment

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Get Premium | $8.99 | one-time |


## Frequently asked questions

### Is Red Koto free?

Red Koto costs $8.99, with no in-app purchases.

### Is Koto Sim free?

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

### Which has better reviews, Red Koto or Koto Sim?

Koto Sim is rated higher. Red Koto averages 1.0 out of 5 from 1 ratings, while Koto Sim averages 5.0 from 4 ratings.

### Do Red Koto or Koto Sim have ads?

Koto Sim shows ads; Red Koto does not.

### Which is updated more often, Red Koto or Koto Sim?

Red Koto ships an update every 6 months, and Koto Sim every 4 weeks. Most recently, Red Koto was updated on October 1, 2026 and Koto Sim 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.*