# NASA PVT+ vs Optimal HRV

The clearest difference is rating: NASA PVT+ at 4.8 against Optimal HRV's 3.0. NASA PVT+ also leads on in-app purchases (none vs 3) and review sentiment (25% vs 17%). Optimal HRV's advantage is update cadence (fortnightly vs every 3 months). On price, ratings volume, ads and device support there is nothing between them.

Both are free to download. Optimal HRV sells 3 in-app purchases, starting at $9.99 per month. NASA PVT+ asks for nothing beyond the download.

NASA PVT+ holds the better App Store score, 4.8 against 3.0. Both are backed by a comparable volume of ratings — 10 and 24 respectively. Written reviews point the same way: 25% of NASA PVT+'s written reviews are positive against 17% of Optimal HRV's.

NASA PVT+ ships an update every 3 months, Optimal HRV fortnightly. The most recent releases landed on October 27, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | NASA PVT+ | Optimal HRV |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (10 ratings)](https://appshunter.io/ios/app/nasa-pvt-plus/id1146834402/reviews)** | [3.0 (24 ratings)](https://appshunter.io/ios/app/optimal-hrv-biofeedback/id1501292206/reviews) |
| Number of ratings | 10 | **24** |
| Positive reviews | **25.0% of reviews** | 16.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Fortnightly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 31 MB | 57 MB |
| Requires iOS | **13.6** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [NASA](https://appshunter.io/developer/355542146) | [Optimal, LLC](https://appshunter.io/developer/1501292205) |

## What reviewers say

### NASA PVT+

[App page](https://appshunter.io/ios/app/nasa-pvt-plus/id1146834402)

This app provides a validated tool for conducting psychomotor vigilance tests, crucial for sleep, alertness, and performance research. It offers multiple study frameworks, including simple tests, basic multi-day studies, and specialized aviation research protocols.

**Highlights:** Psychomotor Vigilance Test (PVT), Karolinska Sleepiness Scale (KSS), Sleep Diary, Simple PVT mode, Basic Study framework, Aviation Study framework

**Features:** Vision Pro support

**In-app purchases:** none


### Optimal HRV

[App page](https://appshunter.io/ios/app/optimal-hrv-biofeedback/id1501292206)

This app uses heart rate variability (HRV) and biofeedback to help you manage stress and improve your body's ability to calm down. It offers guided sessions, personalized breathing rhythms, and real-time feedback to train your nervous system for better stress resilience.

**Highlights:** Real-time HRV data and biofeedback, Personalized breathing rhythm identification, Guided mindfulness sessions, Daily check-ins and progress tracking, External sensor integration for accuracy, Multi-language support

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 month | $9.99 | per month |
| 6 Month | $47.99 | per 6 months |
| One Year | $59.99 | per year |


## Frequently asked questions

### Is NASA PVT+ free?

NASA PVT+ is free to download, with no in-app purchases.

### Is Optimal HRV free?

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

### Which has better reviews, NASA PVT+ or Optimal HRV?

NASA PVT+ is rated higher. NASA PVT+ averages 4.8 out of 5 from 10 ratings, while Optimal HRV averages 3.0 from 24 ratings.

### Do NASA PVT+ or Optimal HRV have ads?

Neither NASA PVT+ nor Optimal HRV shows ads.

### Which is updated more often, NASA PVT+ or Optimal HRV?

NASA PVT+ ships an update every 3 months, and Optimal HRV fortnightly. Most recently, NASA PVT+ was updated on October 27, 2026 and Optimal HRV on October 29, 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.*