# sumFX vs GSDSP Quantum Distortion

The clearest difference is review sentiment: GSDSP Quantum Distortion at 100% against sumFX's 55%. GSDSP Quantum Distortion also leads on rating (5.0 vs 4.4) and update cadence (every 5 weeks vs every 6 months). sumFX's advantage is price ($9.99 vs $14.99). On ratings volume, ads, in-app purchases and monetization model there is nothing between them.

sumFX costs $9.99 and GSDSP Quantum Distortion $14.99 up front. Neither carries in-app purchases, so what you see is what you pay.

GSDSP Quantum Distortion holds the better App Store score, 5.0 against 4.4. Both are backed by a comparable volume of ratings — 12 and 10 respectively. Written reviews point the same way: 55% of sumFX's written reviews are positive against 100% of GSDSP Quantum Distortion's.

sumFX ships an update every 6 months, GSDSP Quantum Distortion every 5 weeks. The most recent releases landed on September 7, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | sumFX | GSDSP Quantum Distortion |
| --- | --- | --- |
| Price | **$9.99** | $14.99 |
| Rating | [4.4 (12 ratings)](https://appshunter.io/ios/app/sumfx/id6450494474/reviews) | **[5.0 (10 ratings)](https://appshunter.io/ios/app/gsdsp-quantum-distortion/id6476145487/reviews)** |
| Number of ratings | **12** | 10 |
| Positive reviews | 54.5% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 5 weeks** |
| Monetization | Paid | Paid |
| Size | 44 MB | 80 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [OSC Audio](https://appshunter.io/developer/1693533681) | [Gustav Scholda](https://appshunter.io/developer/1642323227) |

## What reviewers say

### sumFX

[App page](https://appshunter.io/ios/app/sumfx/id6450494474)

This app is a versatile audio effects processor for musicians. It offers a modular design with multiple high-quality FX modules and customizable slots, allowing for quick creation of unique sounds. Focus on your music with intuitive controls and visual feedback.

**Highlights:** Modular multi-FX processor, 8 high-quality FX modules, 8 FX slots with Wet/Dry control, 2 LFOs per slot, 50+ cross-platform presets, Pre/post waveform view

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

**In-app purchases:** none


### GSDSP Quantum Distortion

[App page](https://appshunter.io/ios/app/gsdsp-quantum-distortion/id6476145487)

Explore four distinct distortion effects—Saturation, BitCrush, Ring Modulation, and Downsampling—blended and controlled via an intuitive XY pad. Shape harmonics, reduce digital resolution, introduce inharmonic motion, and create classic digital degradation for unique audio textures.

**Highlights:** Four distortion algorithms (Saturation, BitCrush, Ring Modulation, Downsampling), Intuitive XY pad for blending effects, Custom waveshaping saturation, BitWarp for tonal variation, Tunable oscillator for ring modulation, Adjustable downsampling rate and jitter, AUv3 audio effect plugin

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is sumFX free?

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

### Is GSDSP Quantum Distortion free?

GSDSP Quantum Distortion costs $14.99, with no in-app purchases.

### Which has better reviews, sumFX or GSDSP Quantum Distortion?

GSDSP Quantum Distortion is rated higher. sumFX averages 4.4 out of 5 from 12 ratings, while GSDSP Quantum Distortion averages 5.0 from 10 ratings.

### Do sumFX or GSDSP Quantum Distortion have ads?

Neither sumFX nor GSDSP Quantum Distortion shows ads.

### Which is updated more often, sumFX or GSDSP Quantum Distortion?

sumFX ships an update every 6 months, and GSDSP Quantum Distortion every 5 weeks. Most recently, sumFX was updated on September 7, 2026 and GSDSP Quantum Distortion on September 22, 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.*