# JAX MIDI ModulePlayer vs ThereminAir

The clearest difference is price: ThereminAir at $3.99 against JAX MIDI ModulePlayer's $29.99. ThereminAir also leads on rating (5.0 vs 4.2) and update cadence (every 11 days vs every 6 months). JAX MIDI ModulePlayer's advantage is ratings volume (5 vs 1) and iOS requirement (14.0 vs 17.0). On ads, in-app purchases and device support there is nothing between them.

JAX MIDI ModulePlayer costs $29.99 and ThereminAir $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ThereminAir holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: JAX MIDI ModulePlayer has 5 ratings behind it against 1, so its average is the more settled of the two.

JAX MIDI ModulePlayer ships an update every 6 months, ThereminAir every 11 days. The most recent releases landed on October 19, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | JAX MIDI ModulePlayer | ThereminAir |
| --- | --- | --- |
| Price | $29.99 | **$3.99** |
| Rating | [4.2 (5 ratings)](https://appshunter.io/ios/app/jax-midi-moduleplayer/id1628626015/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/thereminair-theremin-synth/id6772935515/reviews)** |
| Number of ratings | **5** | 1 |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 11 days** |
| Monetization | Paid | **Free** |
| Size | 24 MB | 2 MB |
| Requires iOS | **14.0** | 17.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Jens Guell](https://appshunter.io/developer/1195004865) | [Tom Pardee](https://appshunter.io/developer/1882976406) |

## What reviewers say

### JAX MIDI ModulePlayer

[App page](https://appshunter.io/ios/app/jax-midi-moduleplayer/id1628626015)

This app functions as a General MIDI compatible multi-timbre synthesizer and file player. It can be used as a sound module for external MIDI signals or as an audio unit within compatible host applications. Create and play back standard MIDI files with over 370 instruments and drum sets.

**Highlights:** GM/GS compatible synthesizer, Plays standard MIDI files, Over 370 instruments and drum sets, 16 MIDI channels simultaneously, Audio Unit (AUv3) support, Standalone host functionality, Universal app for Apple devices

**Features:** Vision Pro support

**In-app purchases:** none


### ThereminAir

[App page](https://appshunter.io/ios/app/thereminair-theremin-synth/id6772935515)

This app transforms your Apple Watch into a unique theremin instrument. Play music through arm gestures, controlling pitch and volume without touching any buttons. Explore different modes and scales to create a variety of sounds.

**Highlights:** Gesture-based pitch and volume control, Pure mode for continuous glide, Scale modes for staying in tune, Adjustable pitch ranges and vibrato depths, Live readout of frequency and note name, Complication for instant play

**Features:** Apple Watch app

**In-app purchases:** none


## Frequently asked questions

### Is JAX MIDI ModulePlayer free?

JAX MIDI ModulePlayer costs $29.99, with no in-app purchases.

### Is ThereminAir free?

ThereminAir costs $3.99, with no in-app purchases.

### Which has better reviews, JAX MIDI ModulePlayer or ThereminAir?

ThereminAir is rated higher. JAX MIDI ModulePlayer averages 4.2 out of 5 from 5 ratings, while ThereminAir averages 5.0 from 1 ratings.

### Do JAX MIDI ModulePlayer or ThereminAir have ads?

Neither JAX MIDI ModulePlayer nor ThereminAir shows ads.

### Which is updated more often, JAX MIDI ModulePlayer or ThereminAir?

JAX MIDI ModulePlayer ships an update every 6 months, and ThereminAir every 11 days. Most recently, JAX MIDI ModulePlayer was updated on October 19, 2026 and ThereminAir on October 11, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*