Comparison

KORG iM1 vs SynthMaster 2

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

Head to head
About

KORG iM1

This app faithfully reproduces the legendary M1 synthesizer, offering its iconic sounds and expanded features for modern music creation. It provides a vast library of presets and intuitive performance tools, making it accessible to both experienced musicians and beginners.

Highlights
  • Faithful reproduction of original M1 sound
  • Expanded filter resonance and 18 effects
  • Gigantic library of 3,300 sounds
  • Intuitive KAOSS pad for performance
  • Smart Sound Browser for quick sound selection
  • Compatible with KORG Gadget
Features
Read full description

A complete reproduction - and more - of the legendary M1 that defined an era. Mobile Digital Synthesizer for the iPad. ● Selected by Apple as "App Store Best of 2015" ● Ranked #1 on the App Store on Top Paid Music category in more than 20 countries! (15/5/27) Since it went on sale in 1988 the legendary M1 music workstation rapidly achieved record-breaking sales, becoming a mainstay of the music scene from the late 1980s and beyond. The common element of electronic instruments that have left their name in history is that they had a unique sound that was difficult if not impossible to replicate. Sounds such as the “M1 Piano” is instantly recognizable and have appeared on countless hit records over many years, and yet these are sounds that could only be produced by the M1. And that’s what you can now have on your iPad! ● A faithful reproduction of the original M1 Sound The PCM data provides the library of the original M1. For the hardware, we analyzed the circuit diagram of the original design, and completely replicated it in software down to the last detailed parameters. Engineers with an exhaustive knowledge of the M1 made careful adjustments in order to obtain the sound of the original unit, something that cannot be obtained simply by sampling the original sounds. ● A continued evolution of the M1 Not content with simply reproducing the original, iM1 provides further evolutionary developments. Synth parts now have the Filter Resonance that was requested at the time of the original. The effect parts, originally consisting of only two effects, have been powered-up to 18 effects. The user interface has also been refreshed with additions such as a KAOSS pad. iM1 is the ultimate version of the KORG M1. ● A gigantic library encompassing 3,300 sounds and 34 cards* In addition to all 19 of the ROM cards originally released for the M1, iM1 also covers the sounds of the M1EX which expanded the internal PCM of the M1, as well as the sounds of the T-series which appeared as an evolution of the M1. There’s also “BEST OF M1”, a selection of 100 great M1 programs. The new “Smart Sound Browser” makes it quick to find the desired sound. You can also view the sounds ranked by how often they are selected by iM1 users around the world. *with all the expansion card installed via in-app purchase ● KAOSS pad lets anybody perform iM1 features a KAOSS pad from the popular KAOSSILATOR, allowing you to perform intuitively just by touching the screen. By using the dual KAOSS pads to play phrases or adjust the sound, even people who are not accustomed to keyboard instruments or knowledgeable about synthesizers can enjoy performing the iM1. There’s also a conventional keyboard, as well as the “Smart Keyboard”, which lets you specify a scale setting and play phrases with a single finger. ● Use with KORG Gadget for song production iM1 can be used together with Gadget, the music production DAW app that won the App Store Best App of 2014 award in Japan. If both apps are installed, you can use iM1 as a sound module within Gadget, taking advantage of the program sounds in iM1 for music production. iM1 also supports Audiobus and Inter-App Audio, so it can also be used for GarageBand etc. ● Connect a MIDI keyboard and use as a sound module In addition to enjoying iM1 on its own, you can connect a USB MIDI keyboard* via a Lightning adaptor and play the iM1 as an external sound module. You can easily take along an even more powerful workstation sound module as part of your iPad-based compact mobile system. *microKEY, nanoKEY etc. ● Interchangeable with the KORG Legacy Collection and the original M1 Sounds that you create in iM1 can be sent from your iPad via iTunes to a Mac/PC. If you have the Legacy Collection M1, you can use those sounds in a DAW. More info at korg.com

About

SynthMaster 2

This powerful software synthesizer offers a vast array of sound design capabilities, including multiple oscillator modes, extensive modulation options, and a wide selection of filters. Explore over 1000 factory presets or create your own unique sounds. Available as a standalone app or AUv3 plugin.

Highlights
  • Multiple oscillator modes (Basic, Additive, Wavetable, Vector)
  • Extensive modulation architecture
  • 6 filter categories
  • Import custom wave files
  • 1000+ factory presets
  • Standalone app and AUv3 plugin
Read full description

KV331 Audio is proud to announce the availability of their award winning software synthesizer SynthMaster 2.9 on iOS platform. As being the first app developed using KV331 Audio’s new cross-platform UI framework, SynthMaster 2 runs as a standalone app or AUv3 plugin on iPads with iOS 11 and above. SynthMaster 2 supports native resolutions of various iPad devices. User interfaces are provided for 9.7, 11 and 12.9 inch iPads in 4 different skins (Blue, White, Dark, Proto). Separate interfaces are provided for the AudioUnit plugin as well. SynthMaster 2 comes with 1000 factory presets designed by world class sound designers such as BigTone, Nori Ubukata, NatLife and Yuli Yolo. Thanks to the comprehensive preset browsing features, users can easily filter presets by author name, bank name, instrument type or preset name and find the sounds that they are looking for. There’s also an IAP Shop, which lets users purchase additional sounds: 1. "Desktop Presets Upgrade": This IAP adds all factory presets in SynthMaster 2.9, increasing the total preset count to 2000. 2. "All Expansions Bundle": This IAP adds all current 38 SynthMaster preset expansion banks. Sound Engine: At the heart of SynthMaster 2’s powerful sound engine lies its oscillators, modulators, and filters. Oscillators: The oscillators can operate in 4 different modes to generate sound: 1. In Basic mode, the oscillator plays single cycle waveforms or samples. With the Oscillator Unison turned on, up to 8 voices per oscillator can be played. 2. In Additive mode, 8 Basic oscillators can be stacked up to create richer tones. 3. In Wavetable mode, the oscillator can play wavetables with up to 256 frames. 4. In Vector mode, 4 Basic oscillators are mixed in 2 dimensions. Modulators: Modulators are simply basic oscillators that can be added to other oscillators or modulate other oscillators’ or modulators’ phases. By connecting modulators to other oscillators or modulators, complex FM tones can be synthesized. Importing Wave Files into SynthMaster: While designing sounds, users can easily import wave files into SynthMaster 2. SynthMaster 2 can categorize those files into waveforms, wavetables or multi samples and import them accordingly. Filters: Once the sound is generated by the oscillators it goes through SynthMaster’s filters, which can operate in 6 different categories: Digital, VAnalog, Ladder, Diode Ladder, State Variable and Bite. Custom distortion can be applied before or after the filters as well. Modulation Architecture: SynthMaster 2 features a comprehensive modulation architecture with a wide range of modulation sources: 1. MIDI controls 2. Macros controls 3. 4 ADSR envelopes per layer 4. 4 Multisegmented envelopes per payer 5. 4 LFOs per layer 6. 4 Sequencers per layer 7. 4 Keyscalers per layer There’s real-time visual feedback that lets users see how modulation sources and targets are changing when a note is being played. This is extremely helpful when designing sounds with SynthMaster 2. New modulations can be created easily by dragging and dropping a modulation source onto a knob or slider control. Users can easily see which controls are modulated by a modulation source by clicking on that source. Controls that are being modulated by that source will display modulation amounts. By long pressing a control, the modulation amount can be edited without the need to go through the mod matrix. Arp/Sequencer: SynthMaster features a comprehensive arpeggiator / sequencer with 32 steps. Users can easily create sequences by recording steps one by one. Effects: Each of the 2 layers in SynthMaster has 5 insert effect slots. 13 different types of effects can be instantiated in any of those slots. There are also 2 global effect send busses which can be used to create more complex effect routings.

Screenshots

KORG iM14 screens

Verdict

The call

The clearest difference is price: SynthMaster 2 at $14.99 against KORG iM1's $29.99. SynthMaster 2 also leads on update cadence (every 3 weeks vs every 7 months). KORG iM1's advantage is ads (none vs shown) and review sentiment (82% vs 68%). On rating, ratings volume, 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

KORG iM1 costs $29.99 and SynthMaster 2 $14.99 up front. KORG iM1 sells 2 one-off in-app purchases and SynthMaster 2 sells 32 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.7 for KORG iM1 against 4.8 for SynthMaster 2. Both are backed by a comparable volume of ratings — 1K and 451 respectively. Written reviews are what separate them: 82% of KORG iM1's written reviews are positive against 68% of SynthMaster 2's.

UpkeepUpdate frequency

KORG iM1 ships an update every 7 months, SynthMaster 2 every 3 weeks. The most recent releases landed on October 13, 2026 and October 14, 2026 respectively.

Scorecard6 real differences · 4 level
KORG iM1 versus SynthMaster 2: the parameters behind the verdict, then further details
ParameterKORG iM1SynthMaster 2
Price$29.99$14.99 — better
Rating4.7 (1K ratings)4.8 (451 ratings) — better
Positive reviews81.5% of reviews — better68.5% of reviews
Number of ratings1K — better451
Update frequencyEvery 7 monthsEvery 3 weeks — better
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPad
Requires iOS12.0 — better15
Further details — not scored
Size200 MB918 MB
Age rating4+4+
DeveloperKORG INC.KV331 Audio

Customer experience

KORG iM1

All ratings1,007 ratings
Positive93.8%
Neutral2.3%
Negative3.9%
Written reviews487 reviews
Positive81.5%
Neutral7.4%
Negative11.1%

SynthMaster 2

All ratings407 ratings
Positive94.3%
Neutral2.2%
Negative3.4%
Written reviews111 reviews
Positive68.5%
Neutral16.2%
Negative15.3%

User reviews

KORG iM1

From 1K App Store ratings

What we love

  • 👍 Authentic M1 sound reproduction
  • 💰 Great value for money
  • 🎹 Faithful recreation of the original hardware
  • 🎨 Powerful sound customization options
  • 🔗 Works well with MIDI controllers

Room to improve

  • 🐛 Occasional crashes or stability issues
  • 🔇 Low output volume compared to other apps
  • 🤔 Confusing UI for patch editing and saving
  • 🔴 Missing AUv3 support for integration with DAWs

SynthMaster 2

From 451 App Store ratings

What we love

  • 🚀 Best synth on iPad
  • 👍 Delicious sound
  • 👍 Tremendously powerful synth
  • 👍 Great synth with complex possibilities and great sound(s)
  • 👍 Perfeito

Room to improve

  • 🐛 Auswahl der Modulationsquellen funktioniert nicht richtig
  • 🐛 Echt schlecht
  • 🐛 Broken Preset System for a powerful synth
  • 🐛 Please fix the OSC behavior on Square and Saw
  • 🐛 Preset issues

Bugs and requests

KORG iM1

Reported bugs

3 issues
  • Disappearing or missing purchased sound cards
  • Bluetooth MIDI connectivity issues
  • Compatibility problems with certain iOS versions or devices

Requested features

4 requests
  • Add AUv3 support for better DAW integration
  • Improve preset management and saving capabilities
  • Increase master volume control options
  • Expand sound library with more cards/expansions

SynthMaster 2

Reported bugs

4 issues
  • Presets not loading correctly
  • Modulation not working after loading project
  • Skin resets to default
  • App crashes frequently

Requested features

2 requests
  • Pitch bend/glide for imported samples
  • Integration with AUM audio mixer

In-app purchases

2 purchases

KORG iM1

One-time2
  • M1 Cards Pack$4.99
  • T1 Cards Pack$4.99
32 purchases

SynthMaster 2

One-time32
  • BigTone Tableworks Vol.2$1.99
  • Burak Yeter Synth Sounds Vol1$1.99
  • Aiyn Zahev Expansion 1$1.99
Show 29 more
  • BigTone Tableworks Vol.1$1.99
  • Michael Kastrup Expansion$1.99
  • EDM Stars Volume 1$1.99
  • Nori Ubukata Pop Hits Vol.4$1.99
  • Rob Lee EDM Expansion Vol.2$1.99
  • Alonso Sound Future Rave$1.99
  • Nori Ubukata Pop Hits Vol.1$1.99
  • BigTone Techno Bits Vol.1$1.99
  • Club Sequences Vol.1$2.99
  • Historical Synth Giants Vol.3$2.99
  • Dawn of Electronic Music Vol.2$2.99
  • Nori Ubukata Art Rock Basics$2.99
  • BigTone Analog Basics 02$4.99
  • BigTone Analog Basics$4.99
  • BigTone Signature Sounds Vol.1$4.99
  • NU Sounds of the World$4.99
  • Historical Synth Giants Vol.4$4.99
  • Historical Synth Giants Vol.1$4.99
  • Historical Synth Giants Vol.2$4.99
  • Japan Vintage$4.99
  • NatLife Future Bass Sounds$4.99
  • Danyella EDM Expansion Vol.1$4.99
  • Dawn of Electronic Music Vol.1$4.99
  • Dawn of Electronic Music Vol.3$4.99
  • Rob Lee EDM Expansion Vol.3$4.99
  • Natlife Disco Funk$4.99
  • Insigne Essentials 4 Clubbin$4.99
  • Desktop Presets Upgrade$9.99
  • All Expansions Bundle$49.99

Questions

Is KORG iM1 free?
KORG iM1 costs $29.99, and also offers in-app purchases.
Is SynthMaster 2 free?
SynthMaster 2 costs $14.99, and also offers in-app purchases.
Which has better reviews, KORG iM1 or SynthMaster 2?
SynthMaster 2 is rated higher. KORG iM1 averages 4.7 out of 5 from 1K ratings, while SynthMaster 2 averages 4.8 from 451 ratings.
Do KORG iM1 or SynthMaster 2 have ads?
SynthMaster 2 shows ads; KORG iM1 does not.
Which is updated more often, KORG iM1 or SynthMaster 2?
KORG iM1 ships an update every 7 months, and SynthMaster 2 every 3 weeks. Most recently, KORG iM1 was updated on October 13, 2026 and SynthMaster 2 on October 14, 2026.

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