Last updated: 2026-06-13

Effective date: 2026-06-13

This document is the canonical Privacy Policy for Cadence (the "App"), a mobile app for iOS and Android that helps you build three daily habits — sleep, exercise, and reading — with a coach by your side. The app is operated by Kooku (the "Developer", contact: [email protected]).

The Korean (한국어) version follows the English text. The two versions are intended to convey the same meaning. If they conflict, the English version governs.

English

1. Summary

Cadence is a personal habit coach for three daily habits — sleep, exercise, and reading. It tracks your habits, shows your weekly progress, and gives you a short coach message. It is designed for personal, on-device use:

Health and personal entries (sleep, heart rate, exercise, steps, evening/morning logs) never leave your device. They are stored locally in an SQLite database and only the App reads them.
Anonymous app usage events and crash reports are sent to a third-party analytics provider so we can understand whether the App works and find bugs.
We do not sell, share for advertising, or otherwise disclose your data to anyone.

2. Data we collect and where it goes

What	Source	Where it is stored	Why
Sleep, heart rate, exercise, steps	Apple Health (iOS) / Health Connect (Android), with your explicit per-permission consent	On-device SQLite only	To track your sleep, exercise, and reading habits and show weekly goal progress
Evening check inputs (target bedtime, last caffeine time, screen-off time, optional exercise/reading minutes)	You type or tap them in	On-device SQLite only	The App's core feature
Morning result inputs (morning energy rating, optional memo)	You type or tap them in	On-device SQLite only	To track your sleep quality and morning energy
Anonymous device/install ID (Android `ANDROID_ID`; on iOS a randomly generated install identifier)	Device OS	Sent to PostHog (analytics)	Distinguish unique devices in usage statistics; never linked to a name or email
App version, OS, platform	Device OS	Sent to PostHog (analytics)	Diagnose version-specific issues
Usage events (app opens, evening check submitted, exercise/reading logged, morning result submitted, coach message shown, etc. — without the contents of your health data or memos)	Inside the App	Sent to PostHog (analytics)	Validate the product hypothesis; find broken flows
Crash reports (stack trace, OS version, app version)	Inside the App when an error occurs	Sent to PostHog (analytics)	Find and fix bugs

We do not collect: name, email, phone number, location, contacts, photos, or any direct identifier. We do not read the actual content of your evening/morning notes or your raw health samples on any server.

3. Third parties

PostHog Inc. (analytics, hosted in the United States) — receives the anonymous device/install ID, app version, OS, usage events, and crash reports. Their privacy policy: https://posthog.com/privacy
Apple HealthKit (iOS) / Google Health Connect (Android) — provide sleep, heart rate, exercise, and step data on-device, only after you grant permission per data type. These health frameworks operate entirely on your device.

We have no other third parties (no advertising SDKs, no attribution SDKs, no payment processors, no backend server).

4. Permissions Cadence requests

Permission	Platform	Why
Health access — Apple Health (iOS) / Health Connect (Android): sleep, heart rate, exercise, steps	iOS, Android	To read your sleep and activity so the App can track your habits and weekly goals
Notifications	iOS, Android	To send the evening reminder and other scheduled notifications
Camera	iOS, Android	To scan a book's barcode (ISBN) and auto-fill its title — no photos are taken, stored, or transmitted
Exact alarms, battery-optimization exemption, boot-completed, wake lock (SCHEDULE_EXACT_ALARM, USE_EXACT_ALARM, REQUEST_IGNORE_BATTERY_OPTIMIZATIONS, RECEIVE_BOOT_COMPLETED, WAKE_LOCK)	Android only	So the evening reminder arrives at the exact time you set and survives reboots and battery-saver mode. iOS schedules local notifications without these.