# Caustic vs AudioKit Retro Piano

The clearest difference is price: AudioKit Retro Piano at Free against Caustic's $9.99. AudioKit Retro Piano also leads on rating (4.3 vs 3.6) and update cadence (every 5 weeks vs every 4 months). Caustic's advantage is in-app purchases (none vs 4) and ads (none vs shown). On ratings volume and device support there is nothing between them.

AudioKit Retro Piano is free to download; Caustic costs $9.99 up front. AudioKit Retro Piano sells 4 in-app purchases, starting at $2.99 per 7 days. Caustic asks for nothing beyond the download.

AudioKit Retro Piano holds the better App Store score, 4.3 against 3.6. Both are backed by a comparable volume of ratings — 179 and 158 respectively. Written reviews point the same way: 58% of Caustic's written reviews are positive against 68% of AudioKit Retro Piano's.

Caustic ships an update every 4 months, AudioKit Retro Piano every 5 weeks. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Caustic | AudioKit Retro Piano |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| Rating | [3.6 (179 ratings)](https://appshunter.io/ios/app/caustic/id775735447/reviews) | **[4.3 (158 ratings)](https://appshunter.io/ios/app/audiokit-retro-piano/id1514017716/reviews)** |
| Number of ratings | **179** | 158 |
| Positive reviews | 57.8% of reviews | **68.1% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 4 months | **Every 5 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Best chart rank | **#112** | — |
| Size | 52 MB | 109 MB |
| Requires iOS | **7.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Rejean Poirier](https://appshunter.io/developer/775735450) | [Audiobus Pty Ltd](https://appshunter.io/developer/672585101) |

## What reviewers say

### Caustic

[App page](https://appshunter.io/ios/app/caustic/id775735447)

**Currently charting:** #112 Top Paid · Music (US App Store)

Create music with a virtual synthesizer and sampler rig. Build your sound by adding up to 14 machines, including synths and drum machines. Features a mixer, effects, and a song sequencer for real-time audio production.

**Highlights:** Virtual analog subtractive synthesizer, Multi-sample wave synthesizer, Sampling drum machine, Effects rack with 20 effect types, Mixer desk with EQ and effects, Song sequencer, AudioBus and AudioCopy/Paste support

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

**In-app purchases:** none

**What reviewers like**

- 🚀 Powerful and feature-rich
- 👍 Intuitive workflow
- 🎨 Excellent sound quality
- 💸 Great value for money

**What reviewers complain about**

- 🐛 Compatibility issues with newer iOS versions
- 🔇 No Bluetooth audio support
- 📁 Difficulty accessing/exporting files
- 🔧 Needs more updates and bug fixes

**Reported bugs**

- Crashes and freezes on newer iPhones
- Interface scaling problems on larger screens
- Unresponsive controls in certain scenarios

**Requested features**

- Bluetooth audio support
- Improved file management and export options
- More synth/instrument options
- Expanded effects and mixing capabilities


### AudioKit Retro Piano

[App page](https://appshunter.io/ios/app/audiokit-retro-piano/id1514017716)

Create vintage and modern piano sounds with this synthesizer app. It offers lo-fi effects, custom vinyl noise, and a stacked synth for unique vibes. Express yourself with simple controls and a big sound in a small package.

**Highlights:** Lo-fi and modern piano sounds, Custom vinyl noise and crush effects, Stacked vintage synth pads, Standalone app and AUv3 plugin, MIDI keyboard support, Universal iPhone & iPad app

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly premium | $2.99 | per 7 days |
| Weekly premium | $2.99 | per 7 days |
| Yearly premium | $9.99 | per year |
| Yearly premium | $9.99 | per year |

**What reviewers like**

- 🎵 Beautiful, warm, and rich piano sounds
- ✨ Excellent presets with creative variety
- 🎛️ Simple and intuitive interface
- 🆓 Free or affordable pricing (original release)
- 🔌 AUv3 audio unit support

**What reviewers complain about**

- 💰 Changed to subscription model ($2.99/month)
- 🔒 Added user tracking/spyware concerns
- 🌐 Now requires internet connection
- 🐛 Frequent crashes and instability
- 🔊 Audio clipping and distortion issues

**Reported bugs**

- Infinite loading screen on startup
- Crashes when used as AU in GarageBand and other DAWs
- MIDI keyboard input not recognized
- Audio unit extension not appearing in DAW options
- Presets revert to default when project reopens

**Requested features**

- Attack time control
- Stretch/microtuning options
- Sequencer and arpeggiator integration
- Built-in recording functionality
- Proper state saving in DAWs


## Frequently asked questions

### Is Caustic free?

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

### Is AudioKit Retro Piano free?

AudioKit Retro Piano is free to download, with in-app purchases available.

### Which has better reviews, Caustic or AudioKit Retro Piano?

AudioKit Retro Piano is rated higher. Caustic averages 3.6 out of 5 from 179 ratings, while AudioKit Retro Piano averages 4.3 from 158 ratings.

### Do Caustic or AudioKit Retro Piano have ads?

AudioKit Retro Piano shows ads; Caustic does not.

### Which is updated more often, Caustic or AudioKit Retro Piano?

Caustic ships an update every 4 months, and AudioKit Retro Piano every 5 weeks. Most recently, Caustic was updated on November 1, 2026 and AudioKit Retro Piano on November 3, 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.*