# Rubo Gems vs Viking Synth

The clearest difference is price: Rubo Gems at Free against Viking Synth's $3.99. Rubo Gems also leads on update cadence (every 10 days vs every 4 months). Viking Synth's advantage is rating (4.7 vs 4.1) and in-app purchases (none vs 1). On review sentiment, ratings volume, ads and device support there is nothing between them.

Rubo Gems is free to download; Viking Synth costs $3.99 up front. Rubo Gems sells 1 one-off in-app purchase. Viking Synth asks for nothing beyond the download.

Viking Synth holds the better App Store score, 4.7 against 4.1. Both are backed by a comparable volume of ratings — 31 and 41 respectively. Written reviews point the same way: 69% of Rubo Gems's written reviews are positive against 71% of Viking Synth's.

Rubo Gems ships an update every 10 days, Viking Synth every 4 months. The most recent releases landed on October 22, 2026 and October 20, 2026 respectively.

## The numbers

| Metric | Rubo Gems | Viking Synth |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Rating | [4.1 (31 ratings)](https://appshunter.io/ios/app/rubo-gems/id370135521/reviews) | **[4.7 (41 ratings)](https://appshunter.io/ios/app/viking-synth/id1085274012/reviews)** |
| Number of ratings | 31 | **41** |
| Positive reviews | 69.2% of reviews | **71.2% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 10 days** | Every 4 months |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 234 MB | 11 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Rubotic, Inc.](https://appshunter.io/developer/1569518836) | [Blamsoft, Inc.](https://appshunter.io/developer/1051938244) |

## What reviewers say

### Rubo Gems

[App page](https://appshunter.io/ios/app/rubo-gems/id370135521)

Easily create your own music with a vast library of loop combinations. Whether you're a beginner or a professional, this app offers a simple yet powerful way to craft beats and grooves for any musical experience.

**Highlights:** Easy song creation, Millions of loop combinations, Create beats and grooves, Suitable for novices and professionals, Intuitive swipe interface

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Upgrade | $1.99 | one-time |

**What reviewers like**

- 🎶 Awesome music creation
- 👍 User-friendly interface
- 💡 Great for beginners
- 🎨 Lots of creative possibilities

**What reviewers complain about**

- 🐛 Crashes and bugs
- 🔒 Requires internet connection
- 💰 In-app purchases needed
- 🔀 Confusing UI changes

**Reported bugs**

- App crashes on startup
- Record button doesn't work
- Saved songs deleted after update
- Compatibility issues with newer iOS

**Requested features**

- Add more sound samples
- Improve export/sharing options
- Offline mode support
- Restore previous app layout


### Viking Synth

[App page](https://appshunter.io/ios/app/viking-synth/id1085274012)

This app emulates a classic monophonic analog synthesizer with advanced DSP technology. It features three variable wave oscillators, dual ladder filters, an LFO, and two modulation busses for versatile sound design.  An intuitive interface and extensive preset library make it ideal for creating thick bass and rich lead sounds.

**Highlights:** Three continuously variable wave oscillators, Dual ladder filters (Lowpass/Highpass), Multi-wave LFO, Two modulation busses, Intuitive user interface with expandable controls, 228 presets including Bass, Lead, and Synthwave, State-of-the-art DSP for authentic sound

**In-app purchases:** none

**What reviewers like**

- 🎶 Great sound quality
- 💡 Versatile sound options
- 💰 Excellent value (free)
- 💻 Lightweight and efficient
- 🎹 Good for learning synthesis

**What reviewers complain about**

- ❓ Preset issues
- 🔌 Not a standalone app
- 🐛 Occasional crashes
- 💾 Settings not saving
- 🤷‍♂️ Difficult to find/use

**Reported bugs**

- Presets not showing up
- Presets disappear
- App not showing in AUv3 menu
- Settings not saving after iOS 14 update
- Crashes when opening presets browser

**Requested features**

- More subtle drive mode
- Categorized preset browser
- Polyphony option
- Dark mode
- More apps from developer


## Frequently asked questions

### Is Rubo Gems free?

Rubo Gems is free to download, with in-app purchases available.

### Is Viking Synth free?

Viking Synth costs $3.99, with no in-app purchases.

### Which has better reviews, Rubo Gems or Viking Synth?

Viking Synth is rated higher. Rubo Gems averages 4.1 out of 5 from 31 ratings, while Viking Synth averages 4.7 from 41 ratings.

### Do Rubo Gems or Viking Synth have ads?

Neither Rubo Gems nor Viking Synth shows ads.

### Which is updated more often, Rubo Gems or Viking Synth?

Rubo Gems ships an update every 10 days, and Viking Synth every 4 months. Most recently, Rubo Gems was updated on October 22, 2026 and Viking Synth on October 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.*