Privacy Policy — What a Green Lawn

Effective date: Marts, 2026
Developer: Klaus Jakobsen, Vejen, Denmark
Contact: devjakobsen@gmail.com

1. Overview

What a Green Lawn is a lawn care assistant that helps you decide when to fertilize, mow, overseed, and scarify — based on your local weather and the lawn zones you set up. This policy explains what data the app collects, how it is used, and your rights as a user.

We collect as little as possible. We do not collect your name, email address, or any payment information.

2. Data we collect

2.1 Lawn zone data

When you create a lawn zone, you provide information about that zone (such as grass type and mowing preferences). This data is stored in the cloud so it is available across app sessions. It is linked to an anonymous user ID — not to your name or any personal identifier.

2.2 Fertilizer application logs

When you log a fertilizer application, the date and any details you choose to enter are stored. This data is used to calculate how recently you fertilized and adjust the app's recommendations accordingly.

2.3 Anonymous account

The app uses Firebase Anonymous Authentication. When you first open the app, a random user ID is created automatically. You never register or log in. This ID is used only to keep your data separate from other users' data in the database. It is not linked to your identity.

2.4 Grace period record

When you start the free preview period, a timestamp is stored in the cloud linked to your device. This is used to determine when the preview expires. This record cannot be deleted — this prevents the preview from being reset by reinstalling the app. It contains only a timestamp and a device identifier; no personal information.

2.5 Location

The app requests your location to fetch local weather data and associate it with your lawn zone. Your approximate coordinates and resolved location name (e.g. "Vejen, Danmark") are stored as part of your lawn zone data in the cloud. Your precise GPS coordinates are not stored — only the coordinates used to identify your general area for weather lookups. This data is linked to your anonymous user ID, not to your identity.

2.6 Crash and performance data

If the app crashes, an anonymised crash report is sent to Firebase Crashlytics. This includes technical information such as your device type, operating system version, and a stack trace. It does not include any of your lawn data or personal information.

3. How we use your data

Purpose Data used
Providing personalised recommendations Lawn zone data, fertilizer logs, location (not stored)
Keeping your data across sessions Anonymous user ID
Enforcing the free preview period Grace period timestamp + device identifier
Fixing bugs and improving stability Crash reports (anonymised)

We do not use your data for advertising. We do not sell your data. We do not share your data with third parties except as described in §4.

4. Third-party services

To provide the app, we use the following services:

Google Firebase Stores your lawn data, fertilizer logs, and grace period record, and handles anonymous authentication. Firebase servers are located in the EU or US depending on configuration. Google complies with EU data protection law through Standard Contractual Clauses.
firebase.google.com/support/privacy
Firebase Crashlytics Receives anonymised crash reports.
→ Same privacy policy as above.
OpenWeatherMap Receives your coordinates to return local weather data. They do not receive any of your lawn data.
openweathermap.org/privacy-policy
Apple / Google Handle subscription purchases and billing. We never receive or store your payment information.
apple.com/legal/privacy / policies.google.com/privacy

5. Data retention

Your lawn data and fertilizer logs are retained as long as you use the app. You can delete individual lawn zones from within the app, which removes all associated data. If you want your anonymous account and all associated data permanently deleted, contact us at devjakobsen@gmail.com and we will process the request within 30 days.

The grace period record is retained indefinitely. It contains only a timestamp and device identifier — no personal data.

Crash reports are retained by Firebase Crashlytics for 90 days by default.

6. Your rights

If you are located in the EU or EEA, you have the following rights under GDPR:

To exercise any of these rights, contact us at devjakobsen@gmail.com.

7. Children

This app is not directed at children under 13 and we do not knowingly collect data from children.

8. Changes to this policy

If we make material changes to this policy, we will update the effective date at the top. Continued use of the app after changes are published constitutes acceptance of the updated policy.