Privacy Policy

The short version

Plant Light Meter measures light with your camera. The measuring happens entirely on your phone: the camera image is read for its exposure data and deleted immediately, and no photo of your home is ever sent anywhere unless you deliberately attach one to a correction.

There are no accounts, no advertising, no advertising identifiers, and nothing is sold or shared with data brokers. Your rooms, readings and plants live on your device and nowhere else.

Three things do leave your phone, and only these:

1. 1Anonymous usage statistics and crash reports, so we can tell what gets used and what breaks
2. 2Your approximate coordinates, sent to NASA, only if you allow location, to look up how much daylight your part of the world gets
3. 3Anything you choose to send us: a newsletter signup, or a correction to our plant library

The rest of this page explains each of those precisely.

Camera

The app reads the camera's exposure metadata (shutter speed, ISO and aperture) and computes illuminance from it. This is the core of the product.

To do that, each reading captures a frame to a temporary file, reads its bytes, and deletes the file before the reading is returned. Frames are not stored, not sent, and not retained after the calculation. Holding MEASURE to average takes several frames; each one is handled and deleted the same way.

The only exception is a photo you take deliberately inside the Send a Correction sheet, described below.

The camera is used only while the app is open and only while you are measuring.

Location

Location is optional. If you decline it, everything except the seasonal daylight estimate still works.

If you allow it, the app requests a low-accuracy, while-in-use fix. It uses your coordinates for two things:

• On your device: to model where the sun is, its elevation and path through the year, which is what turns an instantaneous reading into a daily light total (DLI) and a seasonal forecast. Coordinates are stored on your device alongside any room you map, so the room keeps its orientation to the sun.
• Sent to NASA: rounded, to fetch the long-term daylight climatology for your area from the NASA POWER API. The response is cached on your device. NASA receives coordinates and nothing else: no identifier, no reading, nothing that connects the request to you or to any other request.

Your coordinates are never sent to Biotic Instruments and are never attached to analytics.

Usage analytics

The app uses Google Firebase Analytics to record anonymous, aggregate events. There is no account, no identifier we assign, and no advertising ID; the AdSupport framework is not linked, which is why iOS never asks you to allow tracking.

What is recorded is a short list of things happening, with coarse detail: a measurement was taken (with the brightness bucketed into a band, which lens, whether it was live), the plant list was opened, a verdict was shown, a room scan started or failed, a reading was added to a map, a tutorial page was opened, a setting was changed.

Two events carry a little more. When you add a light reading to a room, we record how far that reading fell from what our daylight model expected (as a ratio, like “1.6 times what we predicted”) alongside how bright the model thought that spot was, how far it sat from a spot you had already measured, roughly what time of day it was, and what the sky was doing. It is the only way to find out whether our model is any good in real rooms rather than in ours. The reading itself is never sent, and a ratio says nothing about you or where you live.

What is deliberately not recorded: your actual readings, coordinates, room names, room shapes, plant names, photos, or anything you type.

Firebase collects some standard technical information automatically, including device model, operating system version, app version, country, and a per-installation identifier that is reset if you delete and reinstall the app.

Crash reports

The app uses Google Firebase Crashlytics. When something crashes or throws, it sends the error, the stack trace, and the device and OS version, so we can find and fix it. Crash reports carry no reading data, no location and no personal content.

Newsletter signup (optional)

If you enter your email address in the signup box, we store that address and the word plant-light-meter (so we know where the signup came from) in a private Google Sheet we control. We use it to tell you what we're working on. Nothing else is attached to it. Ask us and we'll delete it.

Send a correction (optional)

If you disagree with a plant's light range, the correction sheet sends us:

• The plant name and the note you write
• The reading you had on screen, if any (foot-candles and DLI)
• The light range our library currently holds for that plant
• A photo, only if you take one

These go to a private Google Sheet, with photos stored in a private Google Drive folder, both controlled by Biotic Instruments. There is no account attached, and we do not attempt to identify who sent a correction. Please don't include personal information in the note; it goes into a spreadsheet we read by hand.

Everything else stays on your device

Your mapped rooms, their shapes and windows, every reading you take, plants you place, your calibration and settings are stored locally on the phone using the operating system's own app storage. They are not backed up to us and we cannot see them. Deleting the app deletes all of it.

What we don't do

• No accounts, logins or passwords
• No advertising, and no advertising identifiers
• No tracking of you across other apps or websites
• No selling or sharing of personal information, in the sense the CCPA uses those words
• No data brokers, no ad networks, no third-party SDKs beyond the Google and NASA services named above

Who else is involved

• Google — Firebase Analytics and Crashlytics; Google Apps Script, Sheets and Drive for the newsletter and correction endpoints. policies.google.com/privacy
• NASA POWER — daylight climatology, queried by coordinate. power.larc.nasa.gov
• Apple — distributes the app through the App Store and TestFlight, and reports its own installation and crash statistics to us in aggregate. apple.com/legal/privacy

Keeping it, and deleting it

Analytics events and crash reports are retained by Firebase under Google's retention settings. Newsletter addresses are kept until you ask us to remove them. Corrections are kept as long as they're useful for maintaining the plant library. On-device data is kept until you delete it or delete the app.

To have anything removed, or to ask what we hold, email info@bioticinstruments.com. If you're in the EU or UK, you have the right to access, correct, export, restrict or erase your personal data, and to complain to your data protection authority. Where we rely on a legal basis, it is your consent for location and for anything you send us, and our legitimate interest in keeping the app working for the anonymous analytics and crash reporting.

You can withdraw location permission at any time in iOS Settings, and the app continues to work without it.

Children

Plant Light Meter is not directed at children under 13, and we do not knowingly collect personal information from them.

Changes

If this policy changes we'll update this page and move the date at the top. Material changes will be noted in the app's release notes.

Contact

For questions about this policy or your data, contact us at info@bioticinstruments.com. For how this website handles data, see our website privacy policy.