# Robot Butter vs Retromulator

The clearest difference is review sentiment: Robot Butter at 100% against Retromulator's 50%. Retromulator's advantage is update cadence (every 3 days vs monthly) and price ($9.99 vs $14.99). On ads, in-app purchases, monetization model and device support there is nothing between them.

Robot Butter costs $14.99 and Retromulator $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Robot Butter ships an update monthly, Retromulator every 3 days. The most recent releases landed on September 19, 2026 and September 20, 2026 respectively.

## The numbers

| Metric | Robot Butter | Retromulator |
| --- | --- | --- |
| Price | $14.99 | **$9.99** |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/robot-butter/id6759990682/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | **100.0% of reviews** | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 days** |
| Monetization | Paid | Paid |
| Size | 7 MB | 67 MB |
| Requires iOS | 17.0 | **15.0** |
| Devices | **iPhone, iPad, Mac, Vision Pro** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Christian Thompson](https://appshunter.io/developer/1511795684) | [DiscoDSP LLC](https://appshunter.io/developer/1465262828) |

## What reviewers say

### Robot Butter

[App page](https://appshunter.io/ios/app/robot-butter/id6759990682)

This audio effect app creates dynamic soundscapes by blending animated modulation, adaptive reverb, and digital textures. It offers a fast, playable interface with direct control over key parameters and tempo-synced movement for evolving sound design.

**Highlights:** AUv3 audio effect for iPhone, iPad, and macOS, Animated modulation engine, Adaptive reverb stage, Tempo-synced LFO matrix, Digital texture effects, Built-in user manual, Factory and user presets

**In-app purchases:** none


### Retromulator

[App page](https://appshunter.io/ios/app/retromulator/id6764767449)

This app recreates legendary vintage synthesizers, samplers, and keyboards through accurate emulation. It functions as a standalone application or an AUv3 plugin, offering classic electronic music hardware sounds on iOS devices.

**Highlights:** Cycle-accurate hardware emulation, AUv3 plugin support, Standalone app functionality, Full MIDI control, ROM firmware loading, Background audio support

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

**In-app purchases:** none


## Frequently asked questions

### Is Robot Butter free?

Robot Butter costs $14.99, with no in-app purchases.

### Is Retromulator free?

Retromulator costs $9.99, with no in-app purchases.

### Do Robot Butter or Retromulator have ads?

Neither Robot Butter nor Retromulator shows ads.

### Which is updated more often, Robot Butter or Retromulator?

Robot Butter ships an update monthly, and Retromulator every 3 days. Most recently, Robot Butter was updated on September 19, 2026 and Retromulator on September 20, 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.*