# O2X vs Harlen

The clearest difference is rating: Harlen at 5.0 against O2X's 4.2. Harlen also leads on in-app purchases (none vs 2) and review sentiment (100% vs 66%). O2X's advantage is ratings volume (68 vs 2). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. O2X sells 2 in-app purchases, starting at $9.99 per month. Harlen asks for nothing beyond the download.

Harlen holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: O2X has 68 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 66% of O2X's written reviews are positive against 100% of Harlen's.

O2X ships an update every 3 weeks, Harlen every 11 days. The most recent releases landed on October 21, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | O2X | Harlen |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.2 (68 ratings)](https://appshunter.io/ios/app/o2x/id1491463207/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/harlen/id6774843017/reviews)** |
| Number of ratings | **68** | 2 |
| Positive reviews | 65.5% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 11 days** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 79 MB | 36 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [O2X Human Performance LLC](https://appshunter.io/developer/1491463206) | [DANIEL VINH NGUYEN](https://appshunter.io/developer/6774843019) |

## What reviewers say

### O2X

[App page](https://appshunter.io/ios/app/o2x/id1491463207)

This app delivers personalized physical and mental training programs designed to meet your specific needs. Access workouts and guidance from a team of over 150 elite athletes, special operations veterans, and academics.

**Highlights:** Customized training programs, Physical training, Mental training, World-class athlete trainers, Special operations veteran trainers, Academic expertise

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $9.99 | per month |
| Yearly Subscription | $99.99 | per year |


### Harlen

[App page](https://appshunter.io/ios/app/harlen/id6774843017)

This app allows athletes to securely connect with their coach, granting access to wearable and health data. Athletes can view their connection status and recent metrics like heart rate, sleep, and steps directly on their coach's dashboard.

**Highlights:** Secure coach linking, Wearable data sync, Health metric sharing, Consent management, Athlete dashboard view

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

**In-app purchases:** none


## Frequently asked questions

### Is O2X free?

O2X is free to download, with in-app purchases available.

### Is Harlen free?

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

### Which has better reviews, O2X or Harlen?

Harlen is rated higher. O2X averages 4.2 out of 5 from 68 ratings, while Harlen averages 5.0 from 2 ratings.

### Do O2X or Harlen have ads?

Neither O2X nor Harlen shows ads.

### Which is updated more often, O2X or Harlen?

O2X ships an update every 3 weeks, and Harlen every 11 days. Most recently, O2X was updated on October 21, 2026 and Harlen on October 17, 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.*