Privacy Policy

LuxMeter is a PPFD and DLI light meter for indoor growers. It reads your phone's ambient-light sensor and converts the lux reading to PPFD on the device. We collect as little as possible and never sell it. This page explains what is stored, why, and what control you have.

What LuxMeter stores

• On your device: your setups (name, area, light schedule, crop and stage, and the lamps you chose from the catalogue), your PPFD readings, grid maps and calibration profiles.
• Optional account: an account identifier (uid) and, if you sign in with e-mail or Google, your e-mail address. Anonymous sign-in stores the identifier only.
• While you are signed in: your setups, readings and grid maps are synced to the cloud. Calibration profiles are never synced.

What LuxMeter does not do

Lux readings from the light sensor are processed on your device. LuxMeter does not use the camera or the microphone, does not read your location, shows no ads, does not use an advertising ID, and has no analytics or crash reporting.

Where your data lives

Your data is stored on your device first. On Android the local database is encrypted at rest with a key held in the device's secure keystore. In the web app, local data stays in your browser's own storage, which is isolated per site but not separately encrypted.

Cloud sync is optional and only runs while you are signed in. Synced data is stored in Google Cloud Firestore, hosted in the European Union, in a Firebase project operated for LuxMeter. Google encrypts it in transit and at rest. Calibration profiles stay on your device.

The lamp catalogue is downloaded from LuxMeter's own hosting (Firebase Hosting). The app sends no account or personal data with that download; as with any web request, the host sees connection data such as your IP address.

To protect LuxMeter's online services from abuse, the app uses Firebase App Check. On Android, Google Play Integrity checks that requests come from a genuine copy of the app on a genuine device; in the web app, Google reCAPTCHA Enterprise checks the browser and how the page is used. These checks run when the app starts, with or without an account, and send device or browser signals to Google. LuxMeter does not receive or store them.

Who we share it with

We do not sell or rent your data and do not share it for advertising. We share data only with the service provider (processor) that runs the online parts of LuxMeter:

• Google (Firebase Authentication for sign-in, Cloud Firestore for synced data, Firebase Hosting for the lamp catalogue, and Firebase App Check (Play Integrity, reCAPTCHA Enterprise) to protect the online services from abuse). Where Google processes data outside the EU, it relies on the transfer safeguards Google provides.

Your rights

• Access and export: export your readings from the app as CSV or PDF.
• Correction: change or delete your setups in the app; for anything else, contact the controller below.
• Deletion: delete your account in the app (see Retention and deletion below).
• Complaint: you may lodge a complaint with your data-protection supervisory authority.

Retention and deletion

Data on your device stays until you delete it or uninstall LuxMeter. Synced data is kept for as long as your account exists.

You can delete your account in the app. This deletes the account and the setups, readings and grid maps synced to the cloud, and clears them from the device you delete it on. Deletion normally finishes at once; if it is interrupted, an automatic clean-up completes it within a day. Other devices signed in to the account stop syncing and clear their copies the next time the app starts.

Calibration profiles are the exception: they describe your phone's light sensor, were never uploaded and contain no personal data, so they stay on the device after account deletion until you uninstall LuxMeter.

Controller and contact

The data controller for LuxMeter is:

• Controller: [Controller name — to be completed before release]
• E-mail: [Controller e-mail address — to be completed before release]
• Postal address: [Controller postal address — to be completed before release]