Comparison

AudioLayer vs ButterSynth

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

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.

Highlights
  • 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
Features
Read full description

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.

About

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.

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
Currently charting
Read full description

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

AudioLayer4 screens
ButterSynth4 screens

Verdict

The call

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

CostPrice · In-app purchases · Ads · Monetization

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.

ReceptionRating · Positive reviews · Number of ratings

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.

UpkeepUpdate frequency

AudioLayer ships an update fortnightly, ButterSynth every 2 months. The most recent releases landed on September 28, 2026 and September 29, 2026 respectively.

Scorecard6 real differences · 5 level
AudioLayer versus ButterSynth: the parameters behind the verdict, then further details
ParameterAudioLayerButterSynth
Price$12.99 — better$19.99
Rating4.4 (179 ratings) — better4.0 (62 ratings)
Positive reviews55.6% of reviews59.6% of reviews — better
Number of ratings179 — better62
Update frequencyFortnightly — betterEvery 2 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
Best chart rank—#177 — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.0 — better14.0
Further details — not scored
Size242 MB468 MB
Age rating4+4+
DeveloperHarry GohsArto Vaarala

Customer experience

AudioLayer

All ratings179 ratings
Positive81.6%
Neutral5.6%
Negative12.8%
Written reviews124 reviews
Positive55.6%
Neutral16.1%
Negative28.2%

ButterSynth

All ratings62 ratings
Positive72.6%
Neutral8.1%
Negative19.4%
Written reviews57 reviews
Positive59.6%
Neutral10.5%
Negative29.8%

User reviews

AudioLayer

From 179 App Store ratings

What 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 ratings

What 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 more
  • 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 more
  • 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 more
  • 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 more
  • 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

1 purchases

AudioLayer

One-time1
  • SoundFont Import$3.99
None

ButterSynth

No in-app purchases

Questions

Is AudioLayer free?
AudioLayer costs $12.99, and also offers in-app purchases.
Is ButterSynth free?
ButterSynth costs $19.99, with no in-app purchases.
Which has better reviews, AudioLayer or ButterSynth?
AudioLayer is rated higher. AudioLayer averages 4.4 out of 5 from 179 ratings, while ButterSynth averages 4.0 from 62 ratings.
Do AudioLayer or ButterSynth have ads?
Neither AudioLayer nor ButterSynth shows ads.
Which is updated more often, AudioLayer or ButterSynth?
AudioLayer ships an update fortnightly, and ButterSynth every 2 months. Most recently, AudioLayer was updated on September 28, 2026 and ButterSynth on September 29, 2026.

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