Comparison

ButterSynth vs FabFilter Twin 3

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

Head to head
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
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.

About

FabFilter Twin 3

This powerful virtual analog synthesizer offers a vast array of sound-shaping tools, including multiple oscillators, filters, and a comprehensive modulation system. Create a wide range of synth sounds with an intuitive interface and a rich factory preset library.

Highlights
  • Four flexible oscillators
  • Four vintage-style filters
  • Extensive modulation system
  • All-new FX section
  • Arpeggiator with groove controls
  • Full-featured preset browser
  • Analog-modelled drift
Read full description

Since its first release in 2005, FabFilter Twin has been famous for its filter quality and oscillator sound. FabFilter Twin 3 expands and improves on its predecessors in every area, including a complete redesign of the GUI and workflow, more and better oscillators and filters, a radically powered-up modulation system, an all-new FX section, and much more. Sonically versatile, supremely intuitive, and spectacularly ‘analog’, Twin 3 is a dream instrument for creating synth sounds of all kinds, from basses, leads, and pads to plucks, drums, effects, and beyond. The Twin 3 app lets you play via the on-screen keyboard or a MIDI keyboard connected to your iPad. To use Twin 3 as a plug-in, you need an AUv3-compatible host app like Auria, AUM or Cubasis. Twin 3 will appear in the list of Audio Unit extensions for instrument plug-ins in the host app. Key features: - Virtual analog synth featuring four flexible oscillators, four filters, six FX modules, and a vast modulation system with a wealth of flexible source signal generators, drag and drop source/target routing, and no limit to the number of modulation assignments that can be made - Fully redesigned, greatly simplified interface with easier workflow - Completely overhauled modulation system with redesigned modulation sources, and floating slot and FX panels - All-new FX section, housing Reverb, Delay, Chorus, Phaser, Drive, and Compressor modules - Arpeggiator with Groove/Legato controls, note order, latch options, and more - Full-featured preset browser, with tags, favorites, and search and filter functions, and new factory preset library - Per Oscillator polyphony mode: each incoming note triggers a different oscillator - Bell, Shelf, and Notch vintage-style EQ filter shapes - 6dB/octave filter slope option - Modulatable filter Cutoff/Peak Offset knobs knobs, for adjusting all filters at once - High Quality mode — 4x oversampling - Transient mode turns Envelope Followers into transient detectors - Curve adjustment handles for EG Attack, Decay, and Release stages - Slider mode (vertical-only operation) and Range setting (toggles between bipolar and unipolar behavior) for XY controllers - Hide all modulation sources except for XY controllers and Sliders at a click - Native sustain pedal support - Even better oscillator and filter sound quality, with analog-modelled drift - Maximum number of voices doubled from 32 to 64 - Lower minimum Envelope Generator Attack, Decay, and Release times - Maximum number of XY controllers/Sliders increased to six - Envelope Generator Threshold, XLFO Balance, and Frequency Offset made available as modulation targets - Modulation sources can be renamed - Maximum number of modulation slots increased to 100 - Legato mode for MIDI-triggered XLFO - Range options added to MIDI Sources: Negative (-1 to 0), Centered (-1 to 1), and Positive (0 to 1) - Carefully designed and curated factory presets, plus the ability to save your own presets - Undo/redo and A/B comparison "FabFilter Twin is one of the best virtual analogues we've heard so far, and at this price point it's well worth the investment!" — Computer Music "Once I found FabFilter Twin, I immediately noticed how great it works and how amazing it sounds!" — George Morel

Screenshots

ButterSynth4 screens

Verdict

The call

The clearest difference is rating: FabFilter Twin 3 at 4.6 against ButterSynth's 4.0. FabFilter Twin 3 also leads on review sentiment (86% vs 59%). ButterSynth's advantage is update cadence (every 2 months vs every 19 months) and price ($19.99 vs $24.99). On ratings volume, ads, in-app purchases and monetization model 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

ButterSynth costs $19.99 and FabFilter Twin 3 $24.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

FabFilter Twin 3 holds the better App Store score, 4.6 against 4.0. Both are backed by a comparable volume of ratings — 63 and 42 respectively. Written reviews point the same way: 59% of ButterSynth's written reviews are positive against 86% of FabFilter Twin 3's.

UpkeepUpdate frequency

ButterSynth ships an update every 2 months, FabFilter Twin 3 every 19 months. Both last shipped on October 27, 2026.

Scorecard5 real differences · 5 level
ButterSynth versus FabFilter Twin 3: the parameters behind the verdict, then further details
ParameterButterSynthFabFilter Twin 3
Price$19.99 — better$24.99
Rating4.0 (63 ratings)4.6 (42 ratings) — better
Positive reviews59.2% of reviews86.2% of reviews — better
Number of ratings63 — better42
Update frequencyEvery 2 months — betterEvery 19 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPod — betteriPad
Requires iOS14.014.0
Further details — not scored
Size468 MB11 MB
Age rating4+4+
DeveloperArto VaaralaFabFilter

Customer experience

ButterSynth

All ratings63 ratings
Positive73.0%
Neutral7.9%
Negative19.0%
Written reviews71 reviews
Positive59.2%
Neutral11.3%
Negative29.6%

FabFilter Twin 3

All ratings40 ratings
Positive92.5%
Neutral2.5%
Negative5.0%
Written reviews29 reviews
Positive86.2%
Neutral6.9%
Negative6.9%

Bugs and requests

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

FabFilter Twin 3

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

ButterSynth

No in-app purchases

None

FabFilter Twin 3

No in-app purchases

Questions

Is ButterSynth free?
ButterSynth costs $19.99, with no in-app purchases.
Is FabFilter Twin 3 free?
FabFilter Twin 3 costs $24.99, with no in-app purchases.
Which has better reviews, ButterSynth or FabFilter Twin 3?
FabFilter Twin 3 is rated higher. ButterSynth averages 4.0 out of 5 from 63 ratings, while FabFilter Twin 3 averages 4.6 from 42 ratings.
Do ButterSynth or FabFilter Twin 3 have ads?
Neither ButterSynth nor FabFilter Twin 3 shows ads.
Which is updated more often, ButterSynth or FabFilter Twin 3?
ButterSynth ships an update every 2 months, and FabFilter Twin 3 every 19 months. Most recently, ButterSynth was updated on October 27, 2026 and FabFilter Twin 3 on October 27, 2026.

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