# Qithesizer vs GSDSP Quantum Delay

The clearest difference is rating: GSDSP Quantum Delay at 4.8 against Qithesizer's 4.1. GSDSP Quantum Delay also leads on review sentiment (100% vs 77%) and iOS requirement (12.0 vs 15.0). Qithesizer's advantage is update cadence (fortnightly vs every 5 weeks) and price ($12.99 vs $14.99). On ratings volume, ads, in-app purchases and monetization model there is nothing between them.

Qithesizer costs $12.99 and GSDSP Quantum Delay $14.99 up front. Neither carries in-app purchases, so what you see is what you pay.

GSDSP Quantum Delay holds the better App Store score, 4.8 against 4.1. Both are backed by a comparable volume of ratings — 11 and 17 respectively. Written reviews point the same way: 77% of Qithesizer's written reviews are positive against 100% of GSDSP Quantum Delay's.

Qithesizer ships an update fortnightly, GSDSP Quantum Delay every 5 weeks. Both last shipped on September 22, 2026.

## The numbers

| Metric | Qithesizer | GSDSP Quantum Delay |
| --- | --- | --- |
| Price | **$12.99** | $14.99 |
| Rating | [4.1 (11 ratings)](https://appshunter.io/ios/app/qithesizer/id6444722040/reviews) | **[4.8 (17 ratings)](https://appshunter.io/ios/app/gsdsp-quantum-delay/id6469328297/reviews)** |
| Number of ratings | 11 | **17** |
| Positive reviews | 76.9% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 5 weeks |
| Monetization | Paid | Paid |
| Size | 29 MB | 94 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Robkoo Information & Technologies Co., Ltd.](https://appshunter.io/developer/987892941) | [Gustav Scholda](https://appshunter.io/developer/1642323227) |

## What reviewers say

### Qithesizer

[App page](https://appshunter.io/ios/app/qithesizer/id6444722040)

This advanced music synthesizer combines virtual analog, wavetable, and physical modeling sound engines. It offers extensive modulation capabilities, a built-in sequencer, and on-screen keyboard for creating complex sounds.

**Highlights:** Multiple sound engines (virtual analog, wavetable, physical modeling), Extensive modulation sources and destinations, Full MIDI mapping, 16-step sequencer with pattern editor, Waveform and dynamic visualizations, On-screen keyboard

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

**In-app purchases:** none


### GSDSP Quantum Delay

[App page](https://appshunter.io/ios/app/gsdsp-quantum-delay/id6469328297)

This app offers a vintage-inspired stereo delay effect with advanced modulation, flexible filtering, and precise timing controls. It allows users to sculpt unique echo textures, from warm analog sounds to complex, evolving soundscapes.

**Highlights:** Vintage-inspired stereo delay, Deep modulation system, Flexible filtering (LPF, HPF, BPF), Precise timing controls (BPM, ms), Switchable stereo/dual mono modes, Advanced modulation sources (LFO, Random, Envelope)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Qithesizer free?

Qithesizer costs $12.99, with no in-app purchases.

### Is GSDSP Quantum Delay free?

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

### Which has better reviews, Qithesizer or GSDSP Quantum Delay?

GSDSP Quantum Delay is rated higher. Qithesizer averages 4.1 out of 5 from 11 ratings, while GSDSP Quantum Delay averages 4.8 from 17 ratings.

### Do Qithesizer or GSDSP Quantum Delay have ads?

Neither Qithesizer nor GSDSP Quantum Delay shows ads.

### Which is updated more often, Qithesizer or GSDSP Quantum Delay?

Qithesizer ships an update fortnightly, and GSDSP Quantum Delay every 5 weeks. Most recently, Qithesizer was updated on September 22, 2026 and GSDSP Quantum Delay 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.*