# Fox + Son Jetmax vs Mychron Telemetry

The clearest difference is in-app purchases: Mychron Telemetry at none against Fox + Son Jetmax's 1. Mychron Telemetry also leads on update cadence (monthly vs every 3 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Fox + Son Jetmax sells 1 in-app purchase, starting at $7.99 per year. Mychron Telemetry asks for nothing beyond the download.

Fox + Son Jetmax ships an update every 3 months, Mychron Telemetry monthly. The most recent releases landed on September 23, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | Fox + Son Jetmax | Mychron Telemetry |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/fox-plus-son-jetmax/id6748326003/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Monthly** |
| Monetization | Subscription | — |
| Size | 16 MB | 87 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | +4 |
| Developer | [Trophy Inc.](https://appshunter.io/developer/1752591571) | [AKlaus Tecnologia LTDA](https://appshunter.io/developer/1616178461) |

## What reviewers say

### Fox + Son Jetmax

[App page](https://appshunter.io/ios/app/fox-plus-son-jetmax/id6748326003)

This application simplifies jetting calculations for Rotax engines, factoring in weather and altitude. It provides racers with precise tuning recommendations, including relative horsepower and an interactive gear chart, to optimize performance on race day.

**Highlights:** Rotax engine jetting calculator, Weather and altitude adjustments, Relative horsepower calculation, Interactive gear chart, Rotax tuning tips

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Yearly | $7.99 | per year |


### Mychron Telemetry

[App page](https://appshunter.io/ios/app/mychron-telemetry/id6764187786)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Fox + Son Jetmax free?

Fox + Son Jetmax is free to download, with in-app purchases available.

### Is Mychron Telemetry free?

Mychron Telemetry is free to download, with no in-app purchases.

### Do Fox + Son Jetmax or Mychron Telemetry have ads?

Neither Fox + Son Jetmax nor Mychron Telemetry shows ads.

### Which is updated more often, Fox + Son Jetmax or Mychron Telemetry?

Fox + Son Jetmax ships an update every 3 months, and Mychron Telemetry monthly. Most recently, Fox + Son Jetmax was updated on September 23, 2026 and Mychron Telemetry on October 5, 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.*