Privacy Policy

Last updated: 2026-07-29

What data Serum stores

When you use Serum, the app stores the following on your device:

• Your regimen: compounds you track, dosages, frequencies, and schedules.
• Your dose log: the timestamp and amount of every dose you record.
• Custom compounds and bundles you create.
• App settings: theme, units, reminder times, Pro entitlement state.
• A purchase receipt from the platform store (Google Play or Apple), held by the platform and queried locally to determine whether Pro is unlocked.

On Android and iOS, the above is saved to the app's private sandbox via the operating system's standard storage APIs. Other apps cannot directly read that sandbox under the normal platform security model. In Serum's web app, it is stored in browser origin storage; browser extensions, profile sync/backup tools, clearing policies, and anyone with access to that browser profile are governed by your browser and device settings.

What Serum does not do

• No user accounts. There is no sign-up, no login, no username.
• No Serum cloud sync. There is no Serum server, and Serum does not upload your tracker data to us.
• No analytics. We do not collect usage metrics, crash reports, device identifiers, or behavioral data.
• No third-party SDKs for tracking. Serum does not embed Firebase Analytics, Mixpanel, Amplitude, Adjust, AppsFlyer, Facebook SDK, or similar.
• No ads. Serum is free (with an optional one-time Pro purchase) and shows zero advertisements.

Platform backup and device migration

• Android cloud backup. Serum's backup rules exclude its complete SharedPreferences store, which contains regimen, dose-history, body-profile, diet, and app-setting data, from Android cloud backup.
• Android device-to-device transfer. Serum permits the same store to move during a user-controlled, local device-to-device setup transfer. On Android 8.1 and earlier, where Android cannot identify that transport, Serum omits the store from backup instead.
• iCloud Backup. After each preference write, Serum marks both its iOS Preferences directory and preference file with Apple's isExcludedFromBackup resource value. Apple describes this as guidance to the operating system rather than a guarantee that an item can never appear on a backup or restored device.
• Web app. Serum does not upload browser-stored tracker data to us. Whether a browser profile, device backup, extension, or enterprise policy copies that local storage is controlled outside Serum.

Network access

Serum connects to the internet only for the following explicit operations:

• In-app purchase. To verify Pro entitlement, the app talks to Google Play Billing (on Android) or the App Store (on iOS). These are operated by Google and Apple under their respective privacy policies.
• Study links. If you tap a citation link on a compound's detail page, your browser opens the linked DOI or PubMed URL. That destination sees a standard browser request; Serum itself sends nothing.

All other app functionality, including the PK math, dose logging, the charts, interaction warnings, and the clinician-ready PDF export, runs offline. You can use Serum in airplane mode indefinitely.

Optional integrations

Serum supports optional integration with your phone's health data store. When you enable this in settings:

• Health Connect (Android). Serum can write dose records to your platform health store after you grant medication-record write access. Serum does not request Health Connect read access. You control access through platform permissions. Health Connect is separate from Serum, and Android lets you export Health Connect data to a cloud provider you choose.
• Reminders. Serum schedules local notifications on your device. These are handled entirely by Android / iOS and never touch our infrastructure (because there is none).
• Export. You can export your regimen as a PDF or CSV, and your full data as a JSON backup. You decide where these files go. Serum does not upload them anywhere.

In-app purchases

Serum Pro is a one-time purchase processed by Google Play Billing or the Apple App Store. The payment itself and any billing records are held by Google or Apple under their own privacy policies. Serum receives only a receipt token that confirms whether the purchase has been made. We do not receive your payment details, card number, or name.

Data you share by choice

If you choose to use the export feature to share a PDF, CSV, or JSON with a clinician or a friend, that file contains your regimen and dose log. Once the file leaves your device, its handling is up to you and the recipient. We have no involvement.

Data retention and deletion

Because Serum stores nothing on our servers, there is nothing for us to retain or delete. On your devices and services:

• Serum's local tracker data persists until you uninstall the app or tap Reset all data in Settings. Copies you transferred to another device or exported are not deleted by that action.
• Free tier users have dose history older than 90 days automatically pruned. Pro users keep unlimited history.
• Health Connect / Apple Health records you wrote through Serum remain in the platform health store under the platform's retention rules; you can delete them directly there.

Children's privacy

Serum is not directed at children under 13. We do not knowingly collect data from children (or from anyone, for that matter). Uninstalling Serum removes its local app data; any separately exported files or records written to a platform health store must be removed from those locations.

International use

Serum is available globally. We operate no data server and do not transfer your tracker data across borders. Apple, Google, a cloud provider you choose for Health Connect export, or a recipient you choose for a Serum export may process their separate copies under their own terms and your settings.

Changes to this policy

If we add functionality that materially changes how data is handled (for example, a Serum-operated sync service), we will update this page and reflect the change in the app before enabling the feature. The "Last updated" date at the top of this document reflects the most recent material revision.

Contact

Questions, concerns, or privacy requests: contact@serumlog.com.

Serum is developed by Leyline Labs LLC.