# ButterSynth vs Fluss

The clearest difference is rating: Fluss at 4.8 against ButterSynth's 4.0. Fluss also leads on price ($13.99 vs $19.99) and review sentiment (78% vs 59%). On ratings volume, update cadence, ads and in-app purchases there is nothing between them.

ButterSynth costs $19.99 and Fluss $13.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Fluss holds the better App Store score, 4.8 against 4.0. Both are backed by a comparable volume of ratings — 63 and 72 respectively. Written reviews point the same way: 59% of ButterSynth's written reviews are positive against 78% of Fluss's.

ButterSynth ships an update every 2 months, Fluss every 3 months. The most recent releases landed on November 11, 2026 and November 12, 2026 respectively.

## The numbers

| Metric | ButterSynth | Fluss |
| --- | --- | --- |
| Price | $19.99 | **$13.99** |
| Rating | [4.0 (63 ratings)](https://appshunter.io/ios/app/buttersynth/id1497419006/reviews) | **[4.8 (72 ratings)](https://appshunter.io/ios/app/fluss-granular-playground/id6443472888/reviews)** |
| Number of ratings | 63 | **72** |
| Positive reviews | 59.2% of reviews | **78.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | Paid | Paid |
| Size | 468 MB | 453 MB |
| Requires iOS | 14.0 | **12** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Arto Vaarala](https://appshunter.io/developer/890886114) | [Bram Bos](https://appshunter.io/developer/325340444) |

## What reviewers say

### 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


### Fluss

[App page](https://appshunter.io/ios/app/fluss-granular-playground/id6443472888)

Explore granular synthesis with a tactile interface. Import, record, or live-process audio to create unique sound textures, drones, and echoes. Features kinetic sliders for dynamic modulation and a unique shimmer feedback effect.

**Highlights:** Granular synthesis engine, Import, record, or live process audio, Kinetic sliders for modulation, Shimmer feedback effect, MIDI playable, Oberheim Xpander inspired filter, Microtonal experiment support

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 💡 Innovative touch interface
- 🎶 Great for soundscapes
- ✨ Unique sound manipulation
- 🎛️ Intuitive controls
- 🎵 Highly playable instrument

**What reviewers complain about**

- 🐛 Crashes frequently
- ⚫ Black screen issue
- 🎧 No audible output
- 🎛️ Not enough control
- 😵 Too much chaos

**Reported bugs**

- Crashes with black screen
- No audible output
- App resets when put in background
- Cyan play head difficult to see on waveform

**Requested features**

- Adjustable layer field per grain
- Record from internal microphone
- More control over grain direction
- BPM settings
- Transition from clean to new sounds


## Frequently asked questions

### Is ButterSynth free?

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

### Is Fluss free?

Fluss costs $13.99, with no in-app purchases.

### Which has better reviews, ButterSynth or Fluss?

Fluss is rated higher. ButterSynth averages 4.0 out of 5 from 63 ratings, while Fluss averages 4.8 from 72 ratings.

### Do ButterSynth or Fluss have ads?

Neither ButterSynth nor Fluss shows ads.

### Which is updated more often, ButterSynth or Fluss?

ButterSynth ships an update every 2 months, and Fluss every 3 months. Most recently, ButterSynth was updated on November 11, 2026 and Fluss on November 12, 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.*