Ketone – Privacy Policy

Overview

Ketone ("we", "our", or "the app") is an intermittent fasting timer app. We are committed to protecting your privacy. This policy explains what data the app collects, how it is used, and your rights.

TL;DR: Most of your health data (weight, mood) stays only on your device. If you use the Community tab, your fasting records are shared with other Ketone users via the cloud. We do not sell your data. We use limited, anonymized analytics to improve the app.

Data We Collect

Stored on device only

• Weight data – weight entries and goal weight you input
• Mood logs – mood ratings you record after a fast
• App preferences – timer style, color theme, notification settings

This data is stored locally using Room database and DataStore and never leaves your device.

Shared with other users (Community tab)

• Fasting records – start time, duration, and fasting stage reached are uploaded to Google Firebase Firestore and displayed to other Ketone users in the Community tab. You can disable community sharing at any time in the app settings.

Collected by third-party services

• Firebase Crashlytics – crash logs and stack traces when the app crashes, to help us fix bugs. Does not include personal health data.
• Firebase Analytics – anonymous usage events (e.g., "fasting started", "weight recorded") to understand how features are used. No personally identifiable information is included.

Permissions We Request

• Physical Activity Recognition – detects transitions between activities (walking, running, cycling) to provide contextual fasting insights. This uses on-device sensors only; raw activity data is not transmitted.
• Post Notifications – sends reminders when you reach fasting milestones (fat burning, ketosis, autophagy, cell regeneration stages).

Third-Party Services

The app integrates the following third-party SDKs, each with their own privacy policies:

• Google Firebase (Analytics, Crashlytics & Firestore)
• Google Play Services

Data Retention & Deletion

Weight and mood data is stored locally on your device. You can delete it at any time by clearing the app's data or uninstalling the app.

Fasting records shared via the Community tab are stored in Firebase Firestore. You can delete your community data by disabling community sharing in the app settings or by contacting us at jjungmin@gmail.com.

Anonymized analytics and crash data retained by Firebase are subject to Google's data retention policies (typically 14 months for Analytics).

Children's Privacy

Ketone is not directed to children under the age of 13. We do not knowingly collect personal information from children.

Changes to This Policy

We may update this privacy policy from time to time. The "Last updated" date at the top of this page reflects the most recent revision. Continued use of the app after changes constitutes acceptance of the updated policy.

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