Motion Synth vs MIDI FX
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Motion Synth
This app turns your iPhone or iPod touch into a musical instrument. Play notes with touch and control sound with motion. It can be used standalone, with other iOS music apps, or even external hardware and laptop software.
- Play notes via touch
- Shape sound through motion
- Control in-app sounds
- Control other iOS music apps
- Control external hardware synths
- Control laptop audio/visual software
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Music through motion: The AUUG Motion Synth transforms your iPhone or iPod touch into an expressive musical instrument that lets you play notes via touch and shape their sound through motion. Visit http://www.auug.com to see a demonstration video. Available here is the free version of the AUUG Motion Synth App, designed to allow users to easily experience motion-based music creation. Follow the in-app video tutorial to learn how to play the musical instrument sounds included with the app (See 'SETUP VIDEO' button). An upgraded version of the app is also available, and has been carefully designed to work with the AUUG Motion Synth Grip. Together, the Motion Synth App and Grip transform your iPhone or iPod touch into a practical and powerful musical instrument. Get yours here: http://www.auug.com/order/ ------ Play in-app sounds, iOS music apps (e.g. GarageBand), or laptop software through movement: The AUUG Motion Synth tracks your movements and screen touches to expressively play in-app musical sounds. The AUUG Motion Synth also allows you to play the sounds of other iOS music apps, giving you access to a vast array of sounds and effects. You can also play external devices like hardware synths or vocal harmonizers as well as control audio or visual software on a laptop (via WiFi or cabled connections). The Motion Synth app is also compatible with the Music IO app, allowing you to control your laptop software via your iPhone cable (Lightning). ------ Use the Motion Synth App by itself or with a Motion Synth Grip: The Motion Synth App has two modes: 1) Single-Key mode (free version): This Motion Synth App mode allows you to quickly engage with motion-based music control, and includes tutorial videos explaining how to use the in-app sounds. 2) Multi-Key mode (upgrade): This Motion Synth App mode is designed to work with the AUUG Motion Synth Grip: a physical holder that securely attaches your iPhone or iPod touch to your hand, thereby improving the dexterity and accuracy with which you can trigger notes via the touch screen.
MIDI FX
This app allows you to control and process MIDI signals for music creation. It offers features like harmonization, transposition, and sequencing, enabling you to control external or virtual synthesizers and create complex musical arrangements.
- MIDI signal processing
- Harmonize and Transpose
- Sequencer for synths
- Delay and Looper
- Filter notes by velocity
- Internal instruments
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Buy once and get the iOS and Mac apps (with Family Sharing) Control your MIDI signals and process them in any combination of ways: Harmonize, Transpose, Arpeggiate, etc... Or use the Sequencer to play any external or virtual synth. Use a MIDI interface to unlock the power of the app to control multiple synths with one keyboard, play one note and generate chords, basslines, etc... Use the delay/looper or filter notes based on velocity or other parameters to send to different synths/effects. A MIDI workstation in your pocket (or your iPad/Mac) You can also use some internal instruments (drums sampler, piano or synth) if you are away from your MIDI gear, and sequence whole songs inside the app, or use other synth apps as input/output for MIDI FX. Your imagination is the limit!
Screenshots
Verdict
The clearest difference is rating: MIDI FX at 5.0 against Motion Synth's 3.5. MIDI FX also leads on update cadence (every 9 days vs every 4 months) and device support (4 vs 2). Motion Synth's advantage is in-app purchases (none vs 1) and ratings volume (40 vs 4). On price, 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
Both are free to download. MIDI FX sells 1 one-off in-app purchase. Motion Synth asks for nothing beyond the download.
MIDI FX holds the better App Store score, 5.0 against 3.5. That said, the two scores are not equally well evidenced: Motion Synth has 40 ratings behind it against 4, so its average is the more settled of the two.
Motion Synth ships an update every 4 months, MIDI FX every 9 days. The most recent releases landed on October 13, 2026 and October 6, 2026 respectively.
| Parameter | Motion Synth | MIDI FX |
|---|---|---|
| Price | Free | Free |
| Rating | 3.5 (40 ratings) | 5.0 (4 ratings) — better |
| Positive reviews | 73.3% of reviews | — |
| Number of ratings | 40 — better | 4 |
| Update frequency | Every 4 months | Every 9 days — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free | Free |
| Devices | iPhone, iPod | iPhone, iPad, iPod, Mac — better |
| Requires iOS | 9.0 — better | 14.7 |
| Further details — not scored | ||
| Size | 48 MB | 263 MB |
| Age rating | 4+ | 4+ |
| Developer | AUUG | Jorge Arroyo |
Customer experience
Motion Synth
MIDI FX
In-app purchases
Motion Synth
No in-app purchases
MIDI FX
- Unlock app$9.99









