Last updated: 12 August 2026
Arc is built on-device first. Your habits, goals and moods live on your phone, and nothing is sent to our servers unless you explicitly turn on a feature that needs it. This policy explains, plainly, what we collect, why, and the controls you have.
Arc ("the app", "we", "us") is a habit and goal tracker for Android, published under the package
com.syntay.arc. This policy applies to the Arc app and its companion surfaces (home-screen
and lock-screen widgets, the Quick Settings tile, and the Wear OS app).
| Data | Why | Where it's stored |
|---|---|---|
| Account details — email address, and a display name if you provide one | Only if you choose to sign up: to create your account, sign you in, and sync your data across your devices if you enable that. Creating an account is entirely optional — habit tracking works without one. | Firebase Authentication (Google Cloud) |
| Your habit content — habits, goals, mood logs, identities, notes, streaks | This is the core of the app — it's the data you create to track yourself | On your device. Copied to the cloud only if you turn on Cloud sync |
| Cloud backup — a copy of the above | So you can restore your data and use it on more than one device | Cloud Firestore, under your own user ID — opt-in, off by default |
| Accountability partner — a short friend code, a shared daily-completion / streak snapshot, and encouragements you send | To let you pair with a friend and cheer each other on | Cloud Firestore — opt-in, only if you use the partner feature |
| Health & activity (optional, via Health Connect) | To auto-complete activity-based habits (e.g. steps, workouts) | Read on your device with your permission; used locally — not uploaded by Arc |
| Purchases — your Arc Plus subscription / purchase state | To unlock Plus features and restore them on your devices | Handled by Google Play Billing — we never see your card or payment details |
We share data only in these limited ways:
On-device data is kept until you delete it or uninstall the app. If you enable cloud sync, your cloud copy is kept while your account is active and is removed when you delete your account (after the grace period noted above).
Data in transit between the app and Firebase is encrypted (TLS). Account access is protected by Firebase Authentication. No method of storage or transmission is 100% secure, but we use industry-standard measures to protect your information.
Arc is intended for a general audience and is not directed at children under 13. We do not knowingly collect personal information from children. If you believe a child has provided us information, contact us and we will delete it.
Arc is available internationally. Where cloud features are used, data is processed on Google Cloud infrastructure, which may be located outside your country. Where applicable law (such as the GDPR) grants you rights to access, correct, export or delete your data, Arc's in-app export and delete controls let you exercise them directly, and you may also contact us.
We may update this policy as the app evolves. We'll revise the "Last updated" date above and, for material changes, surface a notice in the app.
Questions about this policy or your data? Email contact@syntay.com.