Comparison

KG vs Rithmatic

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

Head to head
About

KG

Features
Read full description

[From '80s Legend to Modern Era: Put the Feel of Authentic Hardware in Your Hands] "KG-SQUARE" is an analog modeling synthesizer app that packs the aesthetics and intuitive operation of professional hardware into an iPhone-sized format. While inheriting the simplicity of its predecessor, "FX-SQUARE," this version delivers a massive upgrade to both its sound engine and UI. From thick, punchy synth basses to dreamlike, immersive pads, it features a wide range of high-quality tones ready to elevate modern music production. ◆ Key Features Highly Immersive Hardware-Style UI: Designed with lifelike 3D knobs and LED indicators, giving you the professional feel and excitement of tweaking real gear. KAOSS PHYSICS (XY Pad): Simply glide your finger across the right-side pad to dynamically control Cutoff, Resonance, and effects. Create sweeping, space-like tonal shifts in real time as you play. Two Powerful Effects: Equipped with "REVERB" for deep spatial warmth and "DELAY" to add movement to your echoes. Seamlessly blend them using dedicated knobs. Polished Sound Presets: Carefully selected, massive sounds unique to analog modeling, including MP Bass, MP Lead, MP PolySynth, and more. Smooth Playability: Features responsive mini-keys along with screen-edge protection to prevent accidental touches, keeping you focused entirely on your performance. Perfect as a companion synth for music production, on-the-go sound design, or intuitive finger-play performances. Experience the ultimate analog modeling sound today!

About

Rithmatic

This app is an FM synthesizer with a vast library of classic voices. It allows users to explore, learn, build, and blend sounds, and can be used as a standalone instrument or an AUv3 plugin within DAWs. It offers a visual representation of sound and a patch builder for understanding FM synthesis.

Highlights
  • 36,118 classic DX7 voices included
  • AUv3 plugin for DAWs
  • Patch Builder for learning FM synthesis
  • Sound blending feature
  • On-screen and MIDI keyboard support
  • Arpeggiator and latch functionality
  • WAV recording and export
Features
Read full description

Rithmatic is an FM synthesizer with 36,118 classic DX7 voices built in, and an AUv3 plugin for GarageBand on iPad and your DAW on the Mac. Browse them by family and by character, learn how FM works by watching it shape each one, build and blend your own, and play them from the on-screen keys or a MIDI keyboard. No account, no ads, nothing locked. Built for iPhone Duo: half open, it stands like a keyboard synth, the waves above the fold and long keys on the flat half. IN YOUR DAW • Put it on a track in GarageBand on iPad, or in an Audio Unit host on the Mac such as Ableton Live. • Its window is the app's own Patches screen and Patch Builder, with your library. • Your bank appears as the plugin's presets, and Brightness, Attack, Decay, Release and Feedback can be automated. The patch is saved with your project. A LIBRARY THAT SHIPS FULL • 36,118 unique DX7 voices come with the app: no download, no account, no network. • Start with Essentials: the famous sounds and the songs they're on. • Browse by family, or by character: percussive, plucked, metallic, bright, sustained, swell, evolving, mellow. Or search by name. • Patch of the day: one classic voice each day, in the app and in a widget for iPhone, iPad and Mac. PLAY IT • A DX7-compatible synthesis engine runs inside the app, so every patch plays with nothing plugged in. • Play from the on-screen keys, your Mac's keyboard, or any MIDI keyboard you connect. • Pitch bend, mod wheel, breath, sustain and aftertouch, with aftertouch set to vibrato, tremolo or swell. • Velocity from a MIDI keyboard, or turn it off and choose how hard every note plays. • An arpeggiator (up, down, up and down, random or as played, over up to three octaves) and a latch that holds each key. • Record what you play and share it as a WAV. • Five tunings: equal, just, and Wendy Carlos's Alpha, Beta and Gamma scales. • Light or dark, as your device is set or as you choose. Drag the keys taller or shorter. SEE THE SOUND The waveform follows what you play: each operator's envelope, how hard you hit, the pitch, the LFO's wobble, and a chord as one layer per note. Resize it, go full screen, or watch the output itself in the Scope look. PATCH BUILDER: LEARN HOW FM WORKS FM is famous for being hard to program. The Patch Builder shows you why a sound sounds the way it does. • All six operators on a graph, each cable carrying its wave: see a modulator reshape its carrier as you drag. • Draw a cable and the builder snaps to the nearest of the 32 algorithms, so you learn routing by doing it. • Plain words beside the jargon. Edit each operator's ratio, level, envelope and tuning, the LFO and pitch envelope, or use FEEL: thickness, touch and brightness. BLEND Pick two patches and Rithmatic blends them into eight new ones. Play each, and keep the ones you like. YOUR BANK AND FILES • Gather patches from anywhere into your bank, then drag pads to swap or reorder them. • Export the bank as standard DX7 .syx files. Open .syx banks, or a .zip of them, from Files, Mail, AirDrop or the Finder. • Share a sound as a short clip of it playing, with a card and a code that brings the patch into anyone's Rithmatic. WITH A SYNTH, IF YOU HAVE ONE Hardware is optional. Choose your synth in Settings: • Korg Volca FM2 (firmware 1.10 or later, over MIDI): read its current patch, write to any of its 64 memory slots, back up and restore all 16 sequencer patterns, and capture the whole instrument to a snapshot. • DX7 family: send patches and 32-voice banks to a DX7, TX7, TX802, the original Volca FM or the M-VAVE FM-1 over standard Yamaha voice dumps. FREE AND PRIVATE Every feature is free; tips are optional and unlock nothing. Rithmatic works offline and collects no personal data: no account, no analytics, no ads. KORG and volca are trademarks of Korg Inc., DX7 and TX of Yamaha Corporation, M-VAVE of its owner. Rithmatic is an independent app, not affiliated with or endorsed by any of them.

Screenshots

KG1 screens
Rithmatic4 screens

Verdict

The call

The clearest difference is in-app purchases: KG at none against Rithmatic's 4. Rithmatic's advantage is update cadence (every 2 days vs every 3 weeks) and device support (4 vs 2). On price and ads 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

Both are free to download. Rithmatic sells 4 one-off in-app purchases. KG asks for nothing beyond the download.

UpkeepUpdate frequency

KG ships an update every 3 weeks, Rithmatic every 2 days. The most recent releases landed on October 31, 2026 and November 1, 2026 respectively.

Scorecard4 real differences · 6 level
KG versus Rithmatic: the parameters behind the verdict, then further details
ParameterKGRithmatic
PriceFreeFree
Rating—4.6 (9 ratings) — better
Positive reviews—66.7% of reviews
Number of ratings—9 — better
Update frequencyEvery 3 weeksEvery 2 days — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Free
DevicesiPhone, iPadiPhone, iPad, iPod, Mac — better
Requires iOS26.515.0 — better
Further details — not scored
Size36 MB61 MB
Age rating4+4+
DeveloperKouki YoshimotoMADE WITH BEST PRACTICE LLC

In-app purchases

None

KG

No in-app purchases

4 purchases

Rithmatic

One-time4
  • Small Tip$4.99
  • Medium Tip$9.99
  • Large Tip$19.99
Show 1 more
  • Extra Large Tip$49.99

Questions

Is KG free?
KG is free to download, with no in-app purchases.
Is Rithmatic free?
Rithmatic is free to download, with in-app purchases available.
Do KG or Rithmatic have ads?
Neither KG nor Rithmatic shows ads.
Which is updated more often, KG or Rithmatic?
KG ships an update every 3 weeks, and Rithmatic every 2 days. Most recently, KG was updated on October 31, 2026 and Rithmatic on November 1, 2026.

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