Theremin I/O vs Motio
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Theremin I/O
Transform your iPhone into a touchless musical instrument using your camera and flash. Control sound generation by hand proximity, with options for scales, sound presets, and effects. An in-app purchase enables MIDI controller functionality.
- Touchless instrument control via camera
- Adjustable scales and harmony quantization
- Multiple sound presets with effects
- MIDI controller functionality (in-app purchase)
- Interactive tutorial overlay
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Play with light – Theremin I/O turns your iPhone into a touchless music instrument. It uses your camera and flash to measure the distance to your hand, this signal is then processed by a synthesizer to generate a tone. Features: • Old-school synthesizer • Constrain input to scales (harmony quantization) • 8 sound presets with effect controls • 50+ scale presets • Use as a MIDI controller (requires in-app purchase) • Learn fast with the tutorial overlay For more information visit http://theremin.io
Motio
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Your body is the instrument. Motio is a motion synth for iPhone. Move, tilt, and gesture to shape sound in real time, then go deeper with BODY tracking, FIELD, LiDAR, MIDI, AUv3, and Sound Editor modes. It is not a beat maker or a DAW-style editor. Motio is built for the moment when you want to play sound directly: rotate your wrist, lean into a gesture, bring a hand into camera view, or map motion to MIDI. What you can do: - Play expressive synth presets with device motion - Use BODY tracking for camera-based control - Explore FIELD and magnetic-field control - Perform LiDAR gestures on supported iPhone models - Send MIDI output to compatible music setups - Use Motio as an AUv3 instrument in supported hosts - Open the Sound Editor to shape presets and mappings Motio Pro unlocks all performance modes, every preset, Sound Editor controls, MIDI, and AUv3 instrument access. The annual plan includes a 7-day free trial; monthly is available without a trial. Designed for musicians, sound designers, experimental performers, and curious creators who want an instrument that starts with movement instead of a timeline. Terms of Use: https://motio.thebulb.app/terms Privacy Policy: https://motio.thebulb.app/privacy
Screenshots
Verdict
The clearest difference is price: Motio at Free against Theremin I/O's $2.99. Motio also leads on update cadence (every 2 weeks vs every 24 months). Theremin I/O's advantage is iOS requirement (8.0 vs 26.0). On ads, in-app purchases and device support 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
Motio is free to download; Theremin I/O costs $2.99 up front. Theremin I/O sells 1 one-off in-app purchase and Motio sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.
Theremin I/O ships an update every 24 months, Motio every 2 weeks. The most recent releases landed on October 26, 2026 and October 24, 2026 respectively.
| Parameter | Theremin I/O | Motio |
|---|---|---|
| Price | $2.99 | Free — better |
| Rating | 4.0 (5 ratings) — better | — |
| Positive reviews | 76.9% of reviews | — |
| Number of ratings | 5 — better | — |
| Update frequency | Every 24 months | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Paid | — |
| Devices | iPhone, iPod — better | iPhone |
| Requires iOS | 8.0 — better | 26.0 |
| Further details — not scored | ||
| Size | 18 MB | 10 MB |
| Age rating | +4 | 4+ |
| Developer | FFFF00 Agents AB | Danis Gaiazov |
In-app purchases
Theremin I/O
- Network MIDI$5.99
Motio
- Motio Pro$2.991 Month
- Motio Pro7 Days trial$19.991 Year







