# KG vs Rithmatic

The clearest difference is in-app purchases: KG at none against Rithmatic's 4. Rithmatic's advantage is update cadence (every 2 days vs every 3 weeks) and device support (4 vs 2). On price and ads there is nothing between them.

Both are free to download. Rithmatic sells 4 one-off in-app purchases. KG asks for nothing beyond the download.

KG ships an update every 3 weeks, Rithmatic every 2 days. The most recent releases landed on October 31, 2026 and November 1, 2026 respectively.

## The numbers

| Metric | KG | Rithmatic |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (9 ratings)](https://appshunter.io/ios/app/rithmatic-fm-synth/id6794107110/reviews)** |
| Number of ratings | — | **9** |
| Positive reviews | — | 66.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 2 days** |
| Monetization | — | Free |
| Size | 36 MB | 61 MB |
| Requires iOS | 26.5 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Kouki Yoshimoto](https://appshunter.io/developer/1884780659) | [MADE WITH BEST PRACTICE LLC](https://appshunter.io/developer/6779338119) |

## What reviewers say

### KG

[App page](https://appshunter.io/ios/app/kg-square-virtual-analog-synth/id6776108274)

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

**In-app purchases:** none


### Rithmatic

[App page](https://appshunter.io/ios/app/rithmatic-fm-synth/id6794107110)

This app is an FM synthesizer with a vast library of classic voices. It allows users to explore, learn, build, and blend sounds, and can be used as a standalone instrument or an AUv3 plugin within DAWs. It offers a visual representation of sound and a patch builder for understanding FM synthesis.

**Highlights:** 36,118 classic DX7 voices included, AUv3 plugin for DAWs, Patch Builder for learning FM synthesis, Sound blending feature, On-screen and MIDI keyboard support, Arpeggiator and latch functionality, WAV recording and export

**Features:** Vision Pro support, iPhone Duo support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small Tip | $4.99 | one-time |
| Medium Tip | $9.99 | one-time |
| Large Tip | $19.99 | one-time |
| Extra Large Tip | $49.99 | one-time |


## Frequently asked questions

### Is KG free?

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

### Is Rithmatic free?

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

### Do KG or Rithmatic have ads?

Neither KG nor Rithmatic shows ads.

### Which is updated more often, KG or Rithmatic?

KG ships an update every 3 weeks, and Rithmatic every 2 days. Most recently, KG was updated on October 31, 2026 and Rithmatic on November 1, 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.*