# Zeeon synth vs ButterSynth

The clearest difference is rating: Zeeon synth at 4.8 against ButterSynth's 4.0. Zeeon synth also leads on price ($14.99 vs $19.99) and review sentiment (76% vs 59%). ButterSynth's advantage is in-app purchases (none vs 3). On update cadence, ads, device support and iOS requirement there is nothing between them.

Zeeon synth costs $14.99 and ButterSynth $19.99 up front. Zeeon synth sells 3 one-off in-app purchases. ButterSynth asks for nothing beyond the download.

Zeeon synth holds the better App Store score, 4.8 against 4.0. Both are backed by a comparable volume of ratings — 209 and 63 respectively. Written reviews point the same way: 76% of Zeeon synth's written reviews are positive against 59% of ButterSynth's.

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on October 24, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | Zeeon synth | ButterSynth |
| --- | --- | --- |
| Price | **$14.99** | $19.99 |
| Rating | **[4.8 (209 ratings)](https://appshunter.io/ios/app/zeeon-synth/id1230960440/reviews)** | [4.0 (63 ratings)](https://appshunter.io/ios/app/buttersynth/id1497419006/reviews) |
| Number of ratings | **209** | 63 |
| Positive reviews | **76.0% of reviews** | 59.2% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 27 MB | 468 MB |
| Requires iOS | 15.6 | **14.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [BeepStreet](https://appshunter.io/developer/321412321) | [Arto Vaarala](https://appshunter.io/developer/890886114) |

## What reviewers say

### Zeeon synth

[App page](https://appshunter.io/ios/app/zeeon-synth/id1230960440)

This app is a virtual analog synthesizer that recreates the sound and feel of classic hardware. It features a detailed circuit-modeling engine, powerful modulation, and multiple filter models for rich, organic soundscapes. Explore a vast array of presets and expand your sonic palette with additional sound banks.

**Highlights:** Circuit-modeling engine, Powerful modulation matrix, Dual oscillators with variable waveforms, Multiple filter models, Built-in effects unit, Audio Unit v3 support, Polyphonic step sequencer

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| OI - Exploration Vol. 1 | $3.99 | one-time |
| BB Z-Space | $4.99 | one-time |
| BB Synthwave | $4.99 | one-time |

**What reviewers like**

- 🎨 Excellent sound quality
- 🎹 Intuitive and well-designed interface
- 🔧 Flexible and deep sound design capabilities
- 💻 Seamless integration as an AUv3 plugin
- 🎚️ Smooth and responsive controls

**What reviewers complain about**

- 🐛 Stability issues, crashes on some devices
- 🔌 Compatibility problems with newer iOS versions
- 📂 Preset management could be improved
- 🔀 Lack of MIDI learn and sequencer features
- 🖥️ UI scaling issues on larger iPad displays

**Reported bugs**

- Preset settings not retained after app restart
- Synth reverts to default settings when reopening Logic Pro project
- Crashes and freezes on certain iOS 14+ devices
- Inability to access in-app purchases from within the app

**Requested features**

- Add MIDI learn functionality
- Implement a more robust preset management system
- Include a built-in sequencer with save/load capabilities
- Improve UI scaling and layout for larger iPad screens
- Provide better integration with inter-app audio and Audiobus


### ButterSynth

[App page](https://appshunter.io/ios/app/buttersynth/id1497419006)

This powerful synthesizer app offers a hybrid approach, combining wavetable, FM, and sample-based synthesis. Create unique sounds with a vast sonic range, advanced modulation, and a built-in effects rack. It caters to both experienced sound designers and beginners with extensive presets.

**Highlights:** Hybrid 6-oscillator synthesis (wavetable, FM, sample), Built-in wavetable editor, FM engine with 4 operators, Sample and Granulator engines, 32-slot modulation matrix, Internal FX rack with 16 modules, Extensive preset library

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- ✨ Deep sound design capabilities
- 🎛️ Versatile modulation matrix
- 🔊 Great sound quality
- 💡 Innovative wavetable generator
- 🌟 Serum-like experience

**What reviewers complain about**

- 📱 Fiddly on small screens
- 🐛 Crashes frequently
- 🐛 Disappears in Cubasis
- 🐛 Spikes CPU usage
- 🐛 Crashes on patch change

**Reported bugs**

- App crashing with AUM
- Disappears in Cubasis randomly
- Crashes all the time inside Logic
- Changing a patch spikes CPU to 99%
- Crashes on every patch change

**Requested features**

- MPE popup possible on top of the auv3
- Button to hide built-in keyboard
- Buffer size option
- Additional MIDI mappings (e.g., arpeggiator toggle)
- Sustain pedal support


## Frequently asked questions

### Is Zeeon synth free?

Zeeon synth costs $14.99, and also offers in-app purchases.

### Is ButterSynth free?

ButterSynth costs $19.99, with no in-app purchases.

### Which has better reviews, Zeeon synth or ButterSynth?

Zeeon synth is rated higher. Zeeon synth averages 4.8 out of 5 from 209 ratings, while ButterSynth averages 4.0 from 63 ratings.

### Do Zeeon synth or ButterSynth have ads?

Neither Zeeon synth nor ButterSynth shows ads.

### Which is updated more often, Zeeon synth or ButterSynth?

Zeeon synth ships an update every 2 months, and ButterSynth every 2 months. Most recently, Zeeon synth was updated on October 24, 2026 and ButterSynth on October 21, 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.*