AudioLayer vs ButterSynth
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
AudioLayer
This app is a powerful mobile multi-sampler for music production, offering advanced features for creating and manipulating complex instruments. It integrates seamlessly with iOS production environments and supports iCloud for easy collaboration and storage.
- Streaming Sample Engine (SSE)
- Hierarchical Layer and Zone editing
- Seamless Instrument Switching (SIS)
- Integrated audio sample recorder
- Auto Sampler for hardware synths
- AUv3 AudioUnit integration
- iCloud storage and collaboration
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AudioLayer satisfies the most sought after gap for contemporary music production on iOS devices. AudioLayer is a full featured open standard audio multi-sampler pushing the boundaries beyond what has been available even in the desktop music production worlds. And all this integrated in all relevant iOS production environments especially the emerging AUv3 AudioUnit standard. - SSE - Streaming Sample Engine - The ultra efficient Streaming Sample Engine SSE is capable of playing hundreds of voices of big multi-sampled instruments even in strictly resource limited applications like using multiple instances of AudioLayer in AudioUnit host environments. Innovative features like Sub Sample Looping for perfect loops even in the audible range extend the range of applications even further. - Multiple storage options - The consequent usage of the open file structure of the Files app makes organising even large sample libraries a breeze. Sample recordings and Instrument designs made with AudioLayer are seamlessly available across all your devices and desktop using either iCloud storage or external SSD. The iCloud option opens up new forms of collaborations with musicians all around the world to share your creations and work together. - Multi Scope Editing - To support the creation of complex multi-sampled instruments AudioLayer allows you to use a hierarchical structure of Layers and Zones each with it’s own sound manipulation parameters. A unique element of AudioLayer is the possibility to decide for each Zone at which Scope level your editing apply: For the all Zones in the Instrument, for the Layer only or individually for this Zone only. This opens a whole new world of creative options for sound mangling. For sound manipulation you can use a full set of Filters, Envelopes and LFOs to shape the pitch, timbre and level of the sound of each Zone. SIS - Seamless Instrument Switching The unique architecture of the Streaming Sample Engine allows for instant loading of even complex instruments and makes this switching from one Instrument to the next without cutting off the sound! And this includes of course also different effect settings - Easy Design Workflow - The built in audio sample recorder let you create Instruments on the fly in seconds. The Music Effect AudioUnit / Audiobus effect plugin of AudioLayer let you record multi-samples semi automatically directly inside your preferred host and instantly create an Instrument with the help of several Auto mapping options available. This includes file name based mapping of key ranges and velocities and automatic pitch detection. For the creatives we’ve also integrated a special “Single Cycle Waveform” detector making the use of this special files a breeze. - Auto Sampler feature for easy creation of Sample Instruments from hardware synthesiser. - Versilian Studio Sample Library ( VCSL/VSCO ) with excellent strings and orchestra samples for free download - Exchange libraries with XinematiX App Integration • Stand-alone App • Sample import for EXS24 and SFZ Format • AUv3 AudioUnit Instrument and Music Effect • Inter App Audio • Audiobus 3 Input/Effect with state saving support. • Audio recorder with share function. • Ableton Link compatible.
ButterSynth
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.
- 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
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ButterSynth is a hybrid 6-oscillator wavetable/FM/sample-based AUV3 and standalone synthesizer with a vast sonic range, from gentle pads to screaming leads and basslines. Mix any combination of wavetable, FM, sample and other synthesis engines for one truly massive sound. For the more advanced users, you'll love using ButterSynth's thoughtfully designed interface, incredibly powerful modulation matrix, fully-featured internal FX rack, factory waveform and sample libraries, and almost limitless scope for fun, experimentation and sound design. For less experienced synth programmers, ButterSynth includes a library of hundreds of ready-to-use presets, sparking your creativity to start making music right away. Headline features include - Mix and match any combination of 6 synthesis engines to either emulate your favourite synths of yester-year or build a synth ready for the future. - Dual-wavetable engines also feature 9 phase modes, wave folding, and deep unison controls modelled on vintage hardware synths. - Built-in wavetable editor gives you the ability to tweak, morph, and hand-draw your own custom wavetables, with each wavetable supporting up to 256 frames. - FM engine offers 4 operators with a selection of 12 modulation paths. Each operator can be loaded with any waveform from the factory or user library, and can also self-modulate via the feedback dial. - Sample and Granulator engines both let you load samples (either imported or from the factory library) and control precisely how they are chopped, triggered and layered. Both also feature the same powerful unison modes available in the WT engine. - Highly configurable 32-slot modulation matrix featuring precise mix/max ranges, self-modulation (via the amount target), plus configurable response curves and layer modes. Simply long-tap any parameter to set it as a Mod destination! - Full suite of versatile control sources which includes: 4x MSEG-style looping curve envelopes, 4x LFOs, 4x step sequencers, X/Y pad with motion recording, 8x Macro dials and a powerful arpeggiator inspired by Kirnu Interactive’s Cream. - The EFX rack lets you build your own insert effects chain using any combination of the 16 built-in FX modules. Modules available at launch include delay, reverb, distortion, chorus, OTT compression etc. Note - FX parameters can also be targeted by the mod matrix, unlocking the possibility to program ‘per voice’ modulated effects. - All presets, wavetables, samples and other settings are stored in the Files app, making bulk import/export, backup and community sharing quick and easy. - All of this is housed in an irresistibly designed 4-tab UI that makes synth programming quick and fun.
Screenshots
Verdict
The clearest difference is in-app purchases: ButterSynth at none against AudioLayer's 1. ButterSynth also leads on chart position (#177 vs unranked). AudioLayer's advantage is price ($12.99 vs $19.99) and rating (4.4 vs 4.0). On review sentiment, ratings volume, ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
AudioLayer costs $12.99 and ButterSynth $19.99 up front. AudioLayer sells 1 one-off in-app purchase. ButterSynth asks for nothing beyond the download.
AudioLayer holds the better App Store score, 4.4 against 4.0. Both are backed by a comparable volume of ratings — 179 and 62 respectively. Written reviews complicate that: 56% of AudioLayer's written reviews are positive against 60% of ButterSynth's, so the app with the better star average is not the one people write more warmly about.
AudioLayer ships an update fortnightly, ButterSynth every 2 months. The most recent releases landed on September 28, 2026 and September 29, 2026 respectively.
| Parameter | AudioLayer | ButterSynth |
|---|---|---|
| Price | $12.99 — better | $19.99 |
| Rating | 4.4 (179 ratings) — better | 4.0 (62 ratings) |
| Positive reviews | 55.6% of reviews | 59.6% of reviews — better |
| Number of ratings | 179 — better | 62 |
| Update frequency | Fortnightly — better | Every 2 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases — better | Paid |
| Best chart rank | — | #177 — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 13.0 — better | 14.0 |
| Further details — not scored | ||
| Size | 242 MB | 468 MB |
| Age rating | 4+ | 4+ |
| Developer | Harry Gohs | Arto Vaarala |
Customer experience
AudioLayer
ButterSynth
User reviews
AudioLayer
From 179 App Store ratingsWhat we love
- 🎹 Powerful multi-layer sampling capabilities
- 📥 EXS24 and SFZ file import support
- 🎯 Round-robin functionality for realistic instruments
- ⚡ Efficient performance on older devices
- 🎚️ Comprehensive effects rack with quality sound
Room to improve
- 🐛 Frequent crashes across multiple iOS versions
- ⚠️ Stability issues in AUM and other hosts
- 🔌 High CPU/DSP usage causing performance spikes
- 🔋 Battery drain and device heating
- ❌ Missing undo function
ButterSynth
From 62 App Store ratingsWhat we love
- ✨ Deep sound design capabilities
- 🎛️ Versatile modulation matrix
- 🔊 Great sound quality
- 💡 Innovative wavetable generator
- 🌟 Serum-like experience
Room to improve
- 📱 Fiddly on small screens
- 🐛 Crashes frequently
- 🐛 Disappears in Cubasis
- 🐛 Spikes CPU usage
- 🐛 Crashes on patch change
Bugs and requests
AudioLayer
Reported bugs
17 issues- App crashes on startup (splash screen)
- Reverb and chorus effects cause sound to disappear
- Pitch resets to -24 after stopping Logic Pro playback
- Layer voice polyphony controls not working properly
- SFZ batch import distributes samples incorrectly across layers
Show 12 moreShow fewer
- EXS24 import fails for complex instruments (pianos, drum kits)
- MIDI source names display as 'Unknown Name'
- Plugin window resizing required to access all controls
- Sample end marker positioning doesn't work in all view sizes
- Soundfont import module shows as missing despite purchase
- App becomes unresponsive when loading complex instruments
- Control Change 11 (Expression) not received
- Autosampler function button missing after update
- Settings not saved properly as AUv3 plugin
- Instrument loading defaults to first instrument in host
- Click/pop noises in sustain loops
- Inter-Audio (IAA) compatibility broken
Requested features
17 requests- Time-stretching/pitch-shifting capability
- Program Change MIDI support
- Undo/Redo functionality
- GigaSampler .gig library support
- Soundfont SF2 import (now paid feature)
Show 12 moreShow fewer
- MIDI learn for real-time parameter control
- Expression (CC11) and other CC support
- Multi-output support for individual zone routing
- Batch import and file management improvements
- Instrument selection screen persistence in MIDI mode
- Bit reduction effect for vintage sampler emulation
- Better local file management and folder organization
- Modulation wheel pitch control
- Transposition features
- Disk streaming for larger libraries
- Macro/customizable GUI support
- Purge unused samples function
ButterSynth
Reported bugs
39 issues- 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
Show 34 moreShow fewer
- No audio when rendering or freezing track
- Keyboard doesn't load on iPhone
- iOS18 broke ButterSynth (audio recording issues)
- Failed to load as Auv3
- Crashes as soon as a preset is selected
- Some patches hanging/sounding without input
- CPU spikes to 100% on preset switching
- Audio crackles on preset switching
- Sample module has consistent buzz
- LFOs are extremely simple (no phase offset)
- Square wave LFO is not square (has slew)
- Step sequencer always has glide/slew
- Cannot save custom presets
- No undo function in wave table editor
- AUv3 plugin resets when ButterSynth crashes
- Does not show up as auv3 in Cubasis, AUM, or Audio Evolution
- Crashes regularly even on newest iPad
- Preset changes every time play is pressed
- Not resizing appropriately on smaller screens
- Crashes with unison function in AUM
- White noise on crash with unison
- Sound continues after song stops in GarageBand
- Preset changes on stop, rewind, or play in GarageBand
- Keeps crashing in GarageBand (AUv3)
- Patches in standalone sound different as AUv3
- Crashes when hitting play with arpeggiator/sequencer on iPhone
- No keyboard appears in iPhone standalone mode
- Audio Unit Extension quit error on export
- Lots of crashes in standalone and hosted in AUM
- MIDI not working
- Automation still doesn’t work in Logic Pro
- Random LFO is great for recording sequences
- Preset browser closes each time a new preset is selected
- Works as AUv3 after starting in standalone mode
Requested features
20 requests- 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
Show 15 moreShow fewer
- Longer LFO speed for evolving soundscapes
- Alternative skins/color themes
- Pinable preset browser
- Virtual keyboard to remain active while browser is pinned
- Make app take up whole screen (no black borders)
- Master detune
- Parameter lock
- More presets
- Fix square wave LFO to be truly square
- Fix step sequencer glide/slew for discrete steps
- Undo function in wave table editor
- Filter key follow button
- Adjust envelope curves (especially release)
- Easier way to adjust modulation matrix amount
- Phase distortion inclusion
In-app purchases
AudioLayer
- SoundFont Import$3.99
ButterSynth
No in-app purchases
Questions
Is AudioLayer free?
Is ButterSynth free?
Which has better reviews, AudioLayer or ButterSynth?
Do AudioLayer or ButterSynth have ads?
Which is updated more often, AudioLayer or ButterSynth?
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