# HeartMath vs Project Function

The clearest difference is in-app purchases: Project Function at none against HeartMath's 5. Project Function also leads on device support (4 vs 1) and iOS requirement (15.5 vs 26.0). On price, update cadence and ads there is nothing between them.

Both are free to download. HeartMath sells 4 in-app purchases, starting at $39.00 per year. Project Function asks for nothing beyond the download.

HeartMath ships an update every 3 weeks, Project Function every 6 weeks. The most recent releases landed on September 25, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | HeartMath | Project Function |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (4.6K ratings)](https://appshunter.io/ios/app/heartmath/id6446414998/reviews)** | — |
| Number of ratings | **4.6K** | — |
| Positive reviews | 73.1% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 6 weeks |
| Monetization | Freemium | — |
| Size | 185 MB | 181 MB |
| Requires iOS | 26.0 | **15.5** |
| Devices | iPhone | **iPhone, iPad, iPod, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [HeartMath Inc.](https://appshunter.io/developer/482739914) | [Project Function LLC](https://appshunter.io/developer/1790112444) |

## What reviewers say

### HeartMath

[App page](https://appshunter.io/ios/app/heartmath/id6446414998)

This app helps you manage stress, improve focus, and achieve optimal performance by aligning your heart, mind, and emotions. It offers guided sessions, immersive journeys, and coherence practices based on over 30 years of research.

**Highlights:** Real-time HRV Coherence Measurement, Coherence Training, Scientifically Validated Techniques, Guided Learning Sessions, Progress Tracking, Heart-Brain Coherence Benefits

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| HeartMath Premium | $39.00 | per year |
| HeartMath Premium | $59.00 | per year |
| HeartMath Premium | $79.00 | per year |
| HeartMath Premium | $99.99 | per year |

**What reviewers like**

- 🚀 Huge improvement over previous app
- 👍 Easy to use and highly recommended
- 💡 Loaded with HeartMath techniques and courses
- 👍 Powerful tool for nervous system balance and anxiety reduction
- 👍 Helps achieve a better mental state

**What reviewers complain about**

- 🐛 Connectivity issues with sensor
- 🐛 Sensor not compatible with older devices
- 🐛 App crashes and freezes on newer devices
- 🐛 Inaccurate heart rate and coherence readings
- 🐛 Disruptive screen sleep behavior during sessions

**Reported bugs**

- Sensor connection issues on newer devices
- App crashes and freezes on iPhone 16 Pro
- Inaccurate heart rate and coherence readings
- Screen sleep behavior disrupting sessions

**Requested features**

- Add dark mode option
- Allow playing music/sounds during sessions
- Provide audio feedback on coherence levels
- Add session history customization and details
- Improve sensor compatibility with older devices


### Project Function

[App page](https://appshunter.io/ios/app/project-function/id6740467390)

**Features:** Apple Wallet, Apple Watch app

**In-app purchases:** none


## Frequently asked questions

### Is HeartMath free?

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

### Is Project Function free?

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

### Do HeartMath or Project Function have ads?

Neither HeartMath nor Project Function shows ads.

### Which is updated more often, HeartMath or Project Function?

HeartMath ships an update every 3 weeks, and Project Function every 6 weeks. Most recently, HeartMath was updated on September 25, 2026 and Project Function on September 22, 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.*