Comparison

Theremin I/O vs Motio

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

Head to head
About

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.

Highlights
  • Touchless instrument control via camera
  • Adjustable scales and harmony quantization
  • Multiple sound presets with effects
  • MIDI controller functionality (in-app purchase)
  • Interactive tutorial overlay
Features
Read full description

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

About

Motio

Features
Read full description

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

Theremin I/O3 screens
Motio4 screens

Verdict

The call

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

CostPrice · In-app purchases · Ads · Monetization

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.

UpkeepUpdate frequency

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.

Scorecard3 real differences · 7 level
Theremin I/O versus Motio: the parameters behind the verdict, then further details
ParameterTheremin I/OMotio
Price$2.99Free — better
Rating4.0 (5 ratings) — better—
Positive reviews76.9% of reviews—
Number of ratings5 — better—
Update frequencyEvery 24 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationPaid—
DevicesiPhone, iPod — betteriPhone
Requires iOS8.0 — better26.0
Further details — not scored
Size18 MB10 MB
Age rating+44+
DeveloperFFFF00 Agents ABDanis Gaiazov

In-app purchases

1 purchases

Theremin I/O

One-time1
  • Network MIDI$5.99
2 purchases

Motio

Subscriptions2
  • Motio Pro$2.991 Month
  • Motio Pro7 Days trial$19.991 Year

Questions

Is Theremin I/O free?
Theremin I/O costs $2.99, and also offers in-app purchases.
Is Motio free?
Motio is free to download, with in-app purchases available.
Do Theremin I/O or Motio have ads?
Neither Theremin I/O nor Motio shows ads.
Which is updated more often, Theremin I/O or Motio?
Theremin I/O ships an update every 24 months, and Motio every 2 weeks. Most recently, Theremin I/O was updated on October 26, 2026 and Motio on October 24, 2026.

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