# ARP ODYSSEi vs ButterSynth

The clearest difference is price: ButterSynth at $19.99 against ARP ODYSSEi's $29.99. ButterSynth also leads on in-app purchases (none vs 2) and update cadence (every 2 months vs every 8 months). ARP ODYSSEi's advantage is rating (4.6 vs 4.0) and ratings volume (332 vs 63). On review sentiment, ads and device support there is nothing between them.

ARP ODYSSEi costs $29.99 and ButterSynth $19.99 up front. ARP ODYSSEi sells 2 one-off in-app purchases. ButterSynth asks for nothing beyond the download.

ARP ODYSSEi holds the better App Store score, 4.6 against 4.0. That said, the two scores are not equally well evidenced: ARP ODYSSEi has 332 ratings behind it against 63, so its average is the more settled of the two. Written reviews point the same way: 65% of ARP ODYSSEi's written reviews are positive against 59% of ButterSynth's.

ARP ODYSSEi ships an update every 8 months, ButterSynth every 2 months. The most recent releases landed on October 17, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | ARP ODYSSEi | ButterSynth |
| --- | --- | --- |
| Price | $29.99 | **$19.99** |
| Rating | **[4.6 (332 ratings)](https://appshunter.io/ios/app/arp-odyssei/id1147432809/reviews)** | [4.0 (63 ratings)](https://appshunter.io/ios/app/buttersynth/id1497419006/reviews) |
| Number of ratings | **332** | 63 |
| Positive reviews | **64.9% of reviews** | 59.2% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 8 months | **Every 2 months** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 222 MB | 468 MB |
| Requires iOS | **9.3** | 14.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [KORG INC.](https://appshunter.io/developer/363714046) | [Arto Vaarala](https://appshunter.io/developer/890886114) |

## What reviewers say

### ARP ODYSSEi

[App page](https://appshunter.io/ios/app/arp-odyssei/id1147432809)

Experience the iconic ARP analog synthesizer sound on your mobile device. This app faithfully reproduces the classic hardware with enhanced features like polyphony and built-in effects. Explore new sonic possibilities with its advanced arpeggiator and optional design revisions.

**Highlights:** Faithful circuit modeling of ARP ODYSSEY, Polyphony and chord playing, Programmable step sequencer arpeggiator, Built-in effects, Optional design revisions (Rev1, Rev2, Rev3), Integration with KORG Gadget

**Features:** Family Sharing

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Odyssey Rev1 | $4.99 | one-time |
| Odyssey Rev2 | $4.99 | one-time |

**What reviewers like**

- 🎨 Faithful recreation of the original ARP Odyssey
- 👍 Great sound quality and accurate emulation
- 🎹 Polyphonic and duophonic capabilities
- 🔊 Impressive built-in effects and sequencer
- 💻 Works well as a standalone app and within Gadget

**What reviewers complain about**

- 🔧 Lack of MIDI implementation (no program change, MIDI learn)
- 🔀 Issues with tuning and pitch tracking, especially in Gadget
- 🔒 No AUv3 support, limiting integration with other apps
- 📱 Small controls and interface can be difficult on smaller devices
- 🔋 CPU-intensive, causing performance issues on some devices

**Reported bugs**

- Crashes when trying to import user presets
- Disappearing sound issues
- Arpeggiator not working correctly within Gadget

**Requested features**

- Add AUv3 support for better DAW integration
- Implement MIDI learn and program change functionality
- Improve tuning and pitch tracking, especially in Gadget
- Optimize performance and reduce CPU usage
- Provide larger UI controls and better support for larger iPad screens


### 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 ARP ODYSSEi free?

ARP ODYSSEi costs $29.99, and also offers in-app purchases.

### Is ButterSynth free?

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

### Which has better reviews, ARP ODYSSEi or ButterSynth?

ARP ODYSSEi is rated higher. ARP ODYSSEi averages 4.6 out of 5 from 332 ratings, while ButterSynth averages 4.0 from 63 ratings.

### Do ARP ODYSSEi or ButterSynth have ads?

Neither ARP ODYSSEi nor ButterSynth shows ads.

### Which is updated more often, ARP ODYSSEi or ButterSynth?

ARP ODYSSEi ships an update every 8 months, and ButterSynth every 2 months. Most recently, ARP ODYSSEi was updated on October 17, 2026 and ButterSynth on October 16, 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.*