Comparison

SynthMaster One vs KORG iMono/Poly

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

Head to head
About

SynthMaster One

This powerful wavetable synthesizer app offers an intuitive workflow for creating unique sounds. It features a rich library of wavetables, inspiring presets, and a semi-modular architecture for deep sound design. Easily sync data across devices and integrate with DAWs.

Highlights
  • Wavetable synthesis
  • Semi-modular architecture
  • 650 factory presets
  • AUv3 support
  • Cross-platform cloud sync
  • Real-time modulation feedback
  • 32-step arpeggiator/sequencer
Read full description

SynthMaster One iOS is KV331 Audio's first full blown universal synth app on iOS platform. It's a powerful wavetable synth with an intuitive workflow. With its simple layout, rich wavetable/waveform content and inspiring factory presets library, designing new sounds with SynthMaster One iOS is a joy. SynthMaster One iOS is feature wise identical to the desktop version except the following: * 16 voice polyphony (32 for the desktop version) * Comes with 650 presets (1250 for the desktop version) FEATURES * Universal App: SynthMaster One is now a universal standalone/AUv3 synth app running on iPhone 7 and above. * 650 Factory Presets: SynthMaster One iOS comes with inspiring factory presets from a world class team of sound designers: Arksun, Aiyn Zahev, BigTone Studios, Brian Transeau, Bluffmunkey, Bulent Biyikoglu, Gercek Dorman, Dejavu Sound, Fragment Audio, Kurt Ader, Mirko Ruta, Nori Ubukata, Rob Lee, Ufuk Kevser, Selcuk Ergen, The Machine, Vandalism Sound, Venus Theory, Vorpalsound and Xenos Soundworks * AUv3: SynthMaster One iOS supports AudioUnits V3, allowing multiple instances to run under supporting DAW apps like GarageBand, Cubasis or Beat Maker. * Files App Integration: Easily import/export presets, waveforms or scales using the common file browser UI (requires iOS 11+). * Real-time Modulation Feedback: See in real-time how modulation sources and targets change. This is a very helpful feature when designing sounds! * Cross Platform Cloud Synchronization: Easily synchronize your SynthMaster One related data across multiple platforms (Windows, MacOS, iPad, iPhone) * Semi-Modular Architecture: For each SynthMaster One instance, there are 2 oscillators with 2 sub oscillators, 2 Filters, 4 ADSR Envelopes, 3 LFOs, a powerful 16 step arpeggiator/sequencer and also 11 different effects that can be inserted on to 6 FX insert slots. The sub oscillators can be connected to the oscillators in 5 different modes which let you use it as a regular sub oscillator or do complex modulations such as ring modulation, amplitude modulation, phase modulation or frequency modulation. * 32 Step Arpeggiator/Sequencer: The arpeggiator in SynthMaster One features classic arpeggiator modes such as Up, Down, UpDown, DownUp, UpDown2, DownUp2, AsPlayed as well as Sequence, Chord and Arpeggiate modes. * Wavetable Synthesis: SynthMaster One implements true wavetable synthesis which opens up new possibilities for sound design. It comes with a rich content library with hundreds of waveforms and wavetables. * Stereo Oscillators with up to 16 voices Unison: Each of the 2 oscillators in SynthMaster One have stereo output, and can have up to 16 voices "unison". Using the "voices", "voices mix", "detune curve", "detune spread", "pan stread", "tone spread" and "phase spread" parameters, each oscillator can generate a rich "supersaw" type sound. * Zero Delay Feedback Filters: All of the 4 filter categories in SynthMaster One are developed using the zero delay feedback filter technology. With advanced filter parameters like input gain, drive, acid, filter nonlinearities and up to 4 times oversampling you can get that "analog" sound from the filters! * Rich Set of Effects: SynthMaster One features 11 different effect types: Distortion, LoFi, Ensemble, Phaser, 6 Band EQ, Compressor, Vocoder, Delay, Chorus, Tremolo, Reverb. * Microtuning: SynthMaster One supports Scala tuning, so tuning can be set either for each preset or globally by loading from a Scala tuning file. SynthMaster One comes with 300+ scales ranging from 5 note equal tempered scales to 12 note alternate tuning scales. * Preset Browser: SynthMaster One features a comprehensive preset browser with separate search criterias for instrument type, preset attributes, music style or preset author. SUPPORTS * All 64-bit iPad devices * AUv3 Audio Unit Extensions * Note-per-channel MIDI controllers (MPE) * Ableton Link * Bluetooth LE MIDI Controllers * AirDrop

About

KORG iMono/Poly

Experience a classic analog synthesizer reborn on iOS. This app faithfully reproduces the iconic 4VCO sound engine, offering deep sound design capabilities with virtual patches and multi-effects. Seamlessly integrate it into your music production workflow.

Highlights
  • Faithful reproduction of classic 4VCO analog synthesizer
  • Deep sound design with extensive modulation
  • Eight virtual patches for expanded sound potential
  • Two multi-effect units
  • Quick access to all synth parameters
  • Integration with KORG Gadget
Features
Read full description

Reviving a classic KORG analog synthesizer. The iconic 4VCO synthesizer, reborn on iOS. The Mono/Poly analog synthesizer appeared in 1981 at the same time as the acclaimed Polysix. Not only was it a fat-sounding four-VCO monophonic synthesizer, it featured a revolutionary design that allowed it to also be used as a four-voice polyphonic synthesizer, which helped cement its legendary status. The long-awaited “KORG iMono/Poly” iPad/iPhone app completely reproduces all features of the original Mono/Poly. Four VCOs and a rich array of modulation allow a wide range of detailed sound design. New functionality such as two multi-effects units and eight virtual patches are also provided. In addition, the seamless integration that you expect from KORG’s iOS apps will fit perfectly into your music making process. The Mono/Poly has been reborn for today’s world, bringing you a unique and legendary sound. * Due to differences in CPU speed of iPads / iPhones, iPad 3rd gen/2/iPad mini/iPhone 4s are not supported, only iPad Air/iPhone 5s or later is recommended. [ Features ] • Deep 4VCO sound. A complete reproduction of the classic Mono/Poly The Mono/Poly synthesizer featured four VCOs, a dedicated envelope generator for the VCF, and also sync and cross-modulation, earning it a reputation for its detailed sound-shaping potential and its distinctive character. • Powerful virtual patches, and the latest presets to catch the scene Eight virtual patches provide the ultimate expansion of the Mono/Poly’s distinctive sound-design potential. Two multi-effect units are also provided, allowing you to create complex and broad-ranging sounds with complete freedom. • Quick access to all panels Although iMono/Poly provides a vast number of parameters, it’s designed with a screen structure that provides quick and seamless access to all of them. With a single tap, you can rotate between the main synth & key assign screen and the virtual patch & effect screen. There’s no need to open individual screens for specific functions, or to move back and forth between them. • Produce music in conjunction with KORG Gadget iMono/Poly can be used in conjunction with “KORG Gadget,” the music production DAW app that has won numerous prizes within Japan and around the world. When you install both apps, iMono/Poly appears as the “Montpellier” gadget within KORG Gadget. More info at korg.com

Screenshots

SynthMaster One4 screens
KORG iMono/Poly4 screens

Verdict

The call

The clearest difference is price: SynthMaster One at $9.99 against KORG iMono/Poly's $29.99. SynthMaster One also leads on rating (4.7 vs 4.3) and ratings volume (743 vs 84). On review sentiment, update cadence, ads and in-app purchases 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

SynthMaster One costs $9.99 and KORG iMono/Poly $29.99 up front. SynthMaster One sells 11 one-off in-app purchases and KORG iMono/Poly sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

SynthMaster One holds the better App Store score, 4.7 against 4.3. That said, the two scores are not equally well evidenced: SynthMaster One has 743 ratings behind it against 84, so its average is the more settled of the two. Written reviews point the same way: 64% of SynthMaster One's written reviews are positive against 62% of KORG iMono/Poly's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on October 24, 2026 and October 21, 2026 respectively.

Scorecard3 real differences · 7 level
SynthMaster One versus KORG iMono/Poly: the parameters behind the verdict, then further details
ParameterSynthMaster OneKORG iMono/Poly
Price$9.99 — better$29.99
Rating4.7 (743 ratings) — better4.3 (84 ratings)
Positive reviews63.8% of reviews — better62.4% of reviews
Number of ratings743 — better84
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS10.09.3 — better
Further details — not scored
Size402 MB203 MB
Age rating4+4+
DeveloperKV331 AudioKORG INC.

Customer experience

SynthMaster One

All ratings743 ratings
Positive92.9%
Neutral2.6%
Negative4.6%
Written reviews207 reviews
Positive63.8%
Neutral10.6%
Negative25.6%

KORG iMono/Poly

All ratings84 ratings
Positive81.0%
Neutral6.0%
Negative13.1%
Written reviews141 reviews
Positive62.4%
Neutral16.3%
Negative21.3%

User reviews

SynthMaster One

From 743 App Store ratings

What we love

  • 🚀 Powerful synth engine
  • 👍 Extensive preset library
  • 🎨 Versatile sound design capabilities
  • 💡 Free desktop version expansions on iPad
  • 🎹 Excellent sound quality and tone

Room to improve

  • 🐛 Crashes and stability issues
  • 🔋 Battery drain in background
  • 🤔 Confusing in-app purchase system
  • 👎 UI/UX could use improvement
  • 🔇 Audio issues and no sound

KORG iMono/Poly

From 84 App Store ratings

What we love

  • 🎶 Great sounding synth
  • ✨ Fantastic sound quality
  • 🎵 Amazing features and sounds
  • 💻 Excellent for Gadget integration
  • 💡 Versatile for sound design

Room to improve

  • 🔌 No AUv3 support
  • 🚫 Useless without AUv3
  • 💸 Waste of money without AUv3
  • 📉 Low output volume
  • 🤏 Small controls, difficult manipulation

Bugs and requests

SynthMaster One

Reported bugs

4 issues
  • Stuck notes and MIDI issues
  • Preset loading crashes
  • Restore purchases not working
  • Incompatibility with certain DAWs

Requested features

4 requests
  • Add custom wavetable support
  • Improve MIDI mapping and MPE functionality
  • Optimize performance on older devices
  • Streamline preset management and browsing

KORG iMono/Poly

Reported bugs

15 issues
  • Cannot restore expansion pack
  • Cannot find store tab
  • Scale selection broken
  • User scale does nothing
  • MIDI unstable
Show 10 more
  • Audio pops
  • Monopoly skin removed
  • Does not work with nanokey studio Bluetooth
  • IAA Panel not displaying host link, transport, record buttons
  • MIDI IAA selection not appearing in Cubasis
  • On-screen keyboard plays fixed velocity notes
  • Arpeggiator doesn't work as expected in Gadget
  • User programmed sounds not visible in Gadget
  • Patches sound different in Gadget
  • App does not take advantage of larger iPhone XS Max screen size

Requested features

42 requests
  • AUv3 support
  • Adaptive Cubasis 3 AUv3
  • More iMPC integration
  • Transfer patches to desktop VST
  • Store preset files on device/flash drive
Show 37 more
  • Keyboard portamento to filter cutoff
  • Double tap knob to zero/fine adjust
  • Save mod wheel position in preset
  • Scroll and lock keyboard to key
  • Octave switches on left with large keyboard
  • Key transpose for arpeggiator
  • Undo/redo feature
  • Portamento on/off button
  • Arpeggio rate as mod destination
  • Full-sized keyboard button
  • Turn into AUv3
  • Bring back Monopoly skin
  • Add high-pass filter (HPF)
  • MIDI sync in
  • Export/share sounds
  • Assign right Kaoss pad like left
  • AUv3 version
  • Latch button for ARP patches
  • Random feature
  • Double tap to return dials to 0
  • Right XY pad assignable
  • More extensive external MIDI controller support
  • MPE support
  • More expansion packs
  • Access user patches within Gadget's Montpellier
  • Mod destination for VCO Mod Type
  • MIDI learn for all controls
  • Link on standalone
  • Improve effects quality
  • Add Korg Prophecy
  • Add Trinity, Triton
  • Improve IAA panel functionality
  • MIDI IAA selection from host
  • Fixed velocity on-screen keyboard improvement
  • Tempo synchronization with other apps (IAA, MIDI clock, Ableton Link)
  • Improve UI for larger screens
  • Immaculate skin option

In-app purchases

11 purchases

SynthMaster One

One-time11
  • BigTone Club Construction Set$4.99
  • True Trance Sounds Volume 1$4.99
  • Vandalism Future House$4.99
Show 8 more
  • NatLife Retrowave Sounds Vol.1$4.99
  • Demis Hellen Euphoric Trance$4.99
  • Venus Theory Trap Sounds$4.99
  • Vandalism Shocking Future Bass$4.99
  • NatLife Progressive&Deep Vol.1$4.99
  • Bluffmunkey Cinematic Sounds$4.99
  • Desktop Presets Upgrade$7.99
  • SM One Expansions Bundle$24.99
1 purchases

KORG iMono/Poly

One-time1
  • Expansion Factory Pack$4.99

Questions

Is SynthMaster One free?
SynthMaster One costs $9.99, and also offers in-app purchases.
Is KORG iMono/Poly free?
KORG iMono/Poly costs $29.99, and also offers in-app purchases.
Which has better reviews, SynthMaster One or KORG iMono/Poly?
SynthMaster One is rated higher. SynthMaster One averages 4.7 out of 5 from 743 ratings, while KORG iMono/Poly averages 4.3 from 84 ratings.
Do SynthMaster One or KORG iMono/Poly have ads?
Neither SynthMaster One nor KORG iMono/Poly shows ads.
Which is updated more often, SynthMaster One or KORG iMono/Poly?
SynthMaster One ships an update every 2 months, and KORG iMono/Poly every 2 months. Most recently, SynthMaster One was updated on October 24, 2026 and KORG iMono/Poly on October 21, 2026.

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