Nocturne · last updated 31 July 2026
Nocturne works out a sleep, light and caffeine plan from a roster you enter yourself. The whole engine runs on your phone. This policy sets out the few places any data moves at all.
You can use Nocturne as a guest. In that mode nothing you enter leaves your device: your profile, roster, sleep log and caffeine ledger are stored in the app's own storage on your phone, and deleting the app deletes them.
Signing in — with an email address and password, with Google, or with Apple — exists for one reason: so the same data appears on your other devices. When you are signed in, your profile, shifts, sleep episodes and caffeine entries are mirrored to Google Firebase (Firestore) under an identifier that belongs to your account. Security rules restrict every one of those documents to that account; nothing in the database is readable by another user.
| Data | Collected | Why |
|---|---|---|
| Email address | Only if you sign in | Authentication and account recovery |
| Sleep and shift entries | Only if you sign in | Sync between your own devices |
| Account identifier | Only if you sign in | To attach your data to your account |
| Location | Never | The city is picked from a list; no location permission is requested |
| Advertising / tracking identifiers | Never | There are no ads, no analytics and no third-party trackers |
| Health data from Apple Health | Never | Nocturne does not read HealthKit |
Sunrise and sunset are computed on your phone from a bundled table of cities. Nocturne reads your device's time zone to suggest one — it does not ask for, receive or store your coordinates.
Purchases are processed by Apple or Google. We use RevenueCat to check whether a purchase is active. RevenueCat receives the anonymous app user identifier the store provides and the transaction details; it does not receive your name, email or location. Their policy: revenuecat.com/privacy.
Sleep, light and low-point reminders are scheduled locally by your phone from the plan Nocturne computed. No notification is sent from a server, so nothing about your schedule travels to reach you.
Guest data is deleted with the app. If you have an account, Settings → Account → Delete account removes the account and everything stored under it. That deletion is permanent and is not a soft disable.
Nocturne is not directed at children and does not knowingly collect anything from them.
If this policy changes materially, the date above changes with it. Questions: szymdzie@gmail.com.