# Calibre Biometrics vs Runflake

The clearest difference is in-app purchases: Runflake at none against Calibre Biometrics's 1. Runflake also leads on update cadence (every 3 days vs every 4 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Calibre Biometrics sells 1 in-app purchase, starting at $7.99 per month. Runflake asks for nothing beyond the download.

Calibre Biometrics ships an update every 4 weeks, Runflake every 3 days. Both last shipped on October 24, 2026.

## The numbers

| Metric | Calibre Biometrics | Runflake |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (2 ratings)](https://appshunter.io/ios/app/calibre-biometrics/id6743721886/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 weeks | **Every 3 days** |
| Monetization | Free | — |
| Size | 116 MB | 72 MB |
| Requires iOS | **15.4** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [BreathTaking Tech LLC](https://appshunter.io/developer/1609706657) | [WorkNPLAY Inc.](https://appshunter.io/developer/6810142839) |

## What reviewers say

### Calibre Biometrics

[App page](https://appshunter.io/ios/app/calibre-biometrics/id6743721886)

This app pairs with a wearable device to track and analyze key metabolic and performance metrics like VO2 Max and resting metabolic rate. It provides detailed insights into your body's energy expenditure and fat burning zones. Designed for informational and educational use, it complements professional health guidance.

**Highlights:** View biometric data, Record metabolic information, Analyze VO2 Max, Monitor Resting Metabolic Rate, Track FatMax and Calories, Companion to wearable tracker

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Calibre Premium | $7.99 | per month |


### Runflake

[App page](https://appshunter.io/ios/app/runflake-run-tracker/id6796767414)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Calibre Biometrics free?

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

### Is Runflake free?

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

### Do Calibre Biometrics or Runflake have ads?

Neither Calibre Biometrics nor Runflake shows ads.

### Which is updated more often, Calibre Biometrics or Runflake?

Calibre Biometrics ships an update every 4 weeks, and Runflake every 3 days. Most recently, Calibre Biometrics was updated on October 24, 2026 and Runflake on October 24, 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.*