---
title: "Kajo: HRV, Sleep & Cortisol - Reviews, Revenue and Downloads in Netherlands | Apple App Store"
description: "Your watch gives you data. Nobody tells you what it means.  Heart rate variability. Resting heart rate. Deep sleep versus REM. You look at the numbers, think "forty-two, okay", and carry on exactly as"
---

# Kajo: HRV, Sleep & Cortisol — Netherlands

![Kajo App Icon](https://is1-ssl.mzstatic.com/image/thumb/Purple221/v4/ea/fd/9a/eafd9a31-03b5-4ddb-f4d8-1b6db1cb2d3b/AppIcon-0-0-1x_U007ephone-0-1-85-220.png/434x0w.png)

**Developer:** [Uomagrit Oy](https://apptail.io/developer/uomagrit-oy-OcSdHb)
**Category:** Health Fitness
**Rating:** N/A (0 ratings)
**Price:** €8.99
**Bundle ID:** com.uomagrit.Kajo
**Store:** Apple App Store
**Country:** Netherlands
**Version:** 1.1 (released 2026-07-31)
**Original Release:** 2026-03-05
**Languages:** English

**App Store Link:** [Download on Apple App Store](https://apps.apple.com/nl/app/app/id6758112743)
**AppTail Page:** [https://apptail.io/app/kajo-hrv-sleep-cortisol-ZoOy/netherlands](https://apptail.io/app/kajo-hrv-sleep-cortisol-ZoOy/netherlands)

## Kajo Description
Your watch gives you data. Nobody tells you what it means.

Heart rate variability. Resting heart rate. Deep sleep versus REM. You look at the numbers, think "forty-two, okay", and carry on exactly as you would have anyway.

Kajo is a translator. It reads what is already in Apple Health and turns it into a plan for today.

YOUR OWN BASELINE, NOT AN AVERAGE
The Rhythm Score compares your HRV to your own 30-day baseline — not to a population average, not to an athlete. A number that looks fine for someone else can still mean you are strained. That is the only comparison that matters.

KNOW WHEN TO PUSH
Optimal means your nervous system has capacity today: train hard, take the difficult task. Strained means the opposite. That is not a failure, it is information — and acting on it is how you avoid burning out.

TIMING, NOT WILLPOWER
Based on when you woke and how you slept, Kajo suggests when to delay your first coffee, when to get light, and when to do demanding work. Small timing changes, done consistently.

WIND DOWN
Soundscapes and guided box breathing for the nights when you are in bed and your head is still at work.

PRIVATE BY DESIGN
Kajo reads directly from Apple Health. Nothing is stored on our servers, there is no account to create, and backups stay in your own iCloud.

One-time purchase. No subscription, no data collection.

Medical Disclaimer: Kajo is designed for general wellness and lifestyle purposes only. It is not a medical device and does not offer medical diagnoses or treatment. The Rhythm Score and recommendations are based on general physiological principles and your personal data patterns. Always consult a qualified healthcare professional before making significant changes to your health regimen or if you have concerns about your health.

## Kajo Screenshots
- [Screenshot 1](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/8a/6e/03/8a6e0379-7276-8a3c-77ab-49d5dbe92a58/iPhone_screenshot_1.png/1320x2868.png)
- [Screenshot 2](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/99/a0/6c/99a06c0a-2fb3-7706-cc54-e1e953eb0114/iPhone_screenshot_2.png/1320x2868.png)
- [Screenshot 3](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/98/24/c2/9824c265-7d3c-aac5-696a-7242e960cfdd/iPhone_screenshot_3.png/1320x2868.png)
- [Screenshot 4](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/70/3d/e5/703de597-27b5-c176-af55-3ffb0cc612ed/iPhone_screenshot_4.png/1320x2868.png)
- [Screenshot 5](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/22/2c/f4/222cf4d1-5057-3142-808b-28aa5bbf1f6b/iPhone_screenshot_5.png/1320x2868.png)
- [Screenshot 6](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/05/2d/40/052d4098-28c2-32cb-20cb-94c22879339a/iPhone_screenshot_6.png/1320x2868.png)








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