# Fox + Son Jetmax vs Rotax Utility+

The clearest difference is in-app purchases: Rotax Utility+ at none against Fox + Son Jetmax's 1. Rotax Utility+ also leads on update cadence (weekly vs every 3 months). Fox + Son Jetmax's advantage is iOS requirement (15.1 vs 18.0). On price, ads and device support there is nothing between them.

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

Fox + Son Jetmax ships an update every 3 months, Rotax Utility+ weekly. The most recent releases landed on November 12, 2026 and November 13, 2026 respectively.

## The numbers

| Metric | Fox + Son Jetmax | Rotax Utility+ |
| --- | --- | --- |
| 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 | **Weekly** |
| Monetization | Subscription | — |
| Size | 16 MB | 26 MB |
| Requires iOS | **15.1** | 18.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 12+ |
| Developer | [Trophy Inc.](https://appshunter.io/developer/1752591571) | [BRP-Rotax GmbH & Co KG](https://appshunter.io/developer/1152315346) |

## 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 |


### Rotax Utility+

[App page](https://appshunter.io/ios/app/rotax-utility-plus/id6784265349)

**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 Rotax Utility+ free?

Rotax Utility+ is free to download, with no in-app purchases.

### Do Fox + Son Jetmax or Rotax Utility+ have ads?

Neither Fox + Son Jetmax nor Rotax Utility+ shows ads.

### Which is updated more often, Fox + Son Jetmax or Rotax Utility+?

Fox + Son Jetmax ships an update every 3 months, and Rotax Utility+ weekly. Most recently, Fox + Son Jetmax was updated on November 12, 2026 and Rotax Utility+ on November 13, 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.*