Comparison

M2DX vs S

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

Head to head
About

M2DX

Create music with a powerful 6-operator FM synthesizer. Explore hand-crafted presets or import classic DX7 banks. Use the on-screen keyboard or connect MIDI controllers for a versatile music-making experience.

Highlights
  • 6-operator, 32-algorithm FM synthesis
  • On-screen keyboard with velocity control
  • DX7-format .syx bank import
  • 6-stage FX chain
  • AUv3 plug-in support
  • Native MIDI 2.0 support
Features
Read full description

M2DX is a 6-operator, 32-algorithm FM synthesizer for iPhone, built from the ground up in pure Swift 6. Open it and play immediately — tap the built-in on-screen keyboard and start making sound with M2DX's own hand-crafted presets. No external hardware or MIDI controller is required. The FM engine is a bit-exact port of the open-source Dexed / msfa DSP, verified sample-for-sample against the reference. It is also compatible with the classic DX7 patch format: bring your own DX7-format .syx banks and play them alongside M2DX's originals. KEY FEATURES - Built-in on-screen keyboard with velocity and octave control — play standalone, no hardware needed - 6-operator, 32-algorithm DX7-style FM synthesis - M2DX's own original FM presets, plus DX7-format .syx bank import (bring your own) - A 6-stage FX chain: EQ, Drive, Chorus, Reverb, Stereo, Maximizer - Low-latency audio with AVAudioSourceNode direct rendering - AUv3 plug-in — use M2DX as an Audio Unit (AUv3) in compatible hosts OPTIONAL MIDI (not required to use the app) - Connect any MIDI controller over Bluetooth or USB if you have one - Native MIDI 2.0 — UMP with 16-bit velocity and 32-bit controllers - MIDI-CI Property Exchange — patch names appear on compatible controllers (for example, KORG KeyStage) - MIDI Learn for hands-on control MIDI 2.0 done natively, classic FM done faithfully. The FM engine is built on Dexed / msfa (Apache License 2.0). M2DX is an independent product and is not affiliated with, endorsed by, or sponsored by Yamaha Corporation. DX7 and Yamaha are trademarks of Yamaha Corporation. iOS 18 or later.

About

S

This app is a polyphonic synthesizer that works with specific hardware. It offers a variety of sound engines, filters, and effects for creating unique audio textures. Advanced modulation options and a flexible routing system allow for deep sound design.

Highlights
  • Dual engine slots per voice
  • Multiple sound flavors (analog, wavetable, FM, speech)
  • Classic and Modern filter modes
  • Advanced FX rack
  • Two free-routing LFOs
  • Unified mod matrix
  • Standalone, AU, and AUv3 formats
Features
Read full description

s-2 is a polyphonic synthesizer designed to work with the Roland AIRA Compact S-1. ENGINE Each voice runs two parallel engine slots that mix together. Pick a sound flavor per slot, including: • Classic analog — saw, square, sub, noise, pulse-width • Wavetable • FM • Speech • Chord • Plucked string FILTER AND FX Classic mode runs a vintage-style ladder filter into a simple Delay → Chorus → Reverb chain. Modern mode swaps in a multi-mode SVF (LP / BP / HP) followed by a 3-slot Advanced FX rack with Bitcrusher, Drive, Flanger, Phaser, Auto-Filter, Tape Delay, Plate Reverb and Chorus. MODULATION Two free-routing LFOs (sine / triangle / saw / square / random / noise, with optional clock-sync), a dedicated filter envelope with two destination slots, and a unified mod matrix dialog that visualizes every routing in one place. Click any knob in Learn mode to assign — no digging through menus. FORMATS • Standalone for iOS • Audio Unit (AU) for Logic Pro and other AU hosts • AUv3 plugin for iPad / iPhone in AUM, GarageBand, Cubasis and more - s-2 is an independent third-party application. It is not affiliated with, sponsored by, or endorsed by Roland Corporation. "Roland", "AIRA", "AIRA Compact", and "S-1" are trademarks of Roland Corporation, used here only to describe MIDI compatibility between this app and that hardware.

Screenshots

M2DX4 screens
S3 screens

Verdict

The call

The clearest difference is rating: S at 4.5 against M2DX's 3.7. S also leads on in-app purchases (none vs 1) and iOS requirement (16.0 vs 18.0). M2DX's advantage is update cadence (every 2 days vs every 6 weeks) and review sentiment (25% vs 0%). On price, ratings volume, ads 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

Both are free to download. M2DX sells 1 one-off in-app purchase. S asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

S holds the better App Store score, 4.5 against 3.7. Both are backed by a comparable volume of ratings — 3 and 4 respectively. Written reviews complicate that: 25% of M2DX's written reviews are positive against 0% of S's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

M2DX ships an update every 2 days, S every 6 weeks. The most recent releases landed on October 8, 2026 and October 12, 2026 respectively.

Scorecard5 real differences · 5 level
M2DX versus S: the parameters behind the verdict, then further details
ParameterM2DXS
PriceFreeFree
Rating3.7 (3 ratings)4.5 (4 ratings) — better
Positive reviews25.0% of reviews — better0.0% of reviews
Number of ratings34 — better
Update frequencyEvery 2 days — betterEvery 6 weeks
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreeFree
DevicesiPhoneiPhone, iPad — better
Requires iOS18.016.0 — better
Further details — not scored
Size16 MB17 MB
Age rating4+4+
DeveloperHakaru HiroseMathias Kirkerød

Customer experience

M2DX

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%
Written reviews4 reviews
Positive25.0%
Neutral75.0%
Negative0.0%

S

All ratings4 ratings
Positive75.0%
Neutral25.0%
Negative0.0%
Written reviews1 reviews
Positive0.0%
Neutral100.0%
Negative0.0%

In-app purchases

1 purchases

M2DX

One-time1
  • M2DX Pro Unlock$9.99
None

S

No in-app purchases

Questions

Is M2DX free?
M2DX is free to download, with in-app purchases available.
Is S free?
S is free to download, with no in-app purchases.
Which has better reviews, M2DX or S?
S is rated higher. M2DX averages 3.7 out of 5 from 3 ratings, while S averages 4.5 from 4 ratings.
Do M2DX or S have ads?
Neither M2DX nor S shows ads.
Which is updated more often, M2DX or S?
M2DX ships an update every 2 days, and S every 6 weeks. Most recently, M2DX was updated on October 8, 2026 and S on October 12, 2026.

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