Privacy Policy

1. Overview

This Privacy Policy applies to the Krzyżówka Challenge mobile application ("Application") developed by Paweł Grzejszczak ("Service Provider", "we", "us"), residing in Poland. The Application is offered as an ad-supported free service.

We are committed to protecting your personal data in accordance with the General Data Protection Regulation (GDPR / RODO) and applicable Polish law.

2. What data is collected

Data stored locally on your device only (not transmitted to us or any server):

• Game progress, level history, coin balance
• Avatar and customisation choices
• Application settings (sound, preferences)

Data collected automatically by third-party SDKs on our behalf:

The Application does not collect: precise location data, contacts, photos, microphone or camera input, financial information, or health data.

The Application does not use Artificial Intelligence (AI) technologies to process your personal data.

3. Legal basis for processing (GDPR Art. 6)

We rely on the following legal bases to process personal data:

• Legitimate interests (Art. 6(1)(f)) — processing by Firebase Crashlytics to detect and fix technical errors, which is necessary for the stable operation of the Application.
• Consent (Art. 6(1)(a)) — processing by Firebase Analytics and AdMob for analytics and personalised advertising. You may withdraw consent at any time (see Your rights).

For users under the age of 16, consent must be given or authorised by a parent or legal guardian (see Minors section).

4. Third-party services

The Application integrates the following third-party SDKs, each governed by its own Privacy Policy:

• Google Play Services
• AdMob
• Google Analytics for Firebase
• Firebase Crashlytics

Data processed by these services is transferred to and stored on Google's servers, which may be located outside the European Economic Area. Google LLC participates in the EU–US Data Privacy Framework and applies standard contractual clauses approved by the European Commission.

We may also disclose data when required by law, court order, or to protect the rights and safety of users or the public.

5. Minors & parental consent

The Application is designed for users aged 13 and above. However, under GDPR Article 8 and Polish law, users under the age of 16 require the consent of a parent or legal guardian for any processing of personal data based on consent (e.g. analytics, personalised ads).

We do not knowingly collect personal data from children under 13. If we become aware that a child under 13 has provided personal information, we will take immediate steps to delete it.

6. Your rights under GDPR (Art. 15–22)

As a data subject in the European Union, you have the following rights regarding your personal data:

To exercise any of these rights, contact us at krzyzowka.challenge@gmail.com. We will respond within 30 days.

Opt-out of data collection: You can disable personalised advertising in your device settings (Google Ads settings / Limit Ad Tracking). You can stop all SDK data collection by uninstalling the Application.

7. Data retention

Leaderboard data (nickname, level, XP, avatar ID) is stored in Firebase Firestore and is publicly visible to other players. This data is retained as long as you use the Application.

To request deletion of your leaderboard entry or any other data, please email krzyzowka.challenge@gmail.com with subject "Data Deletion Request" and your in-game nickname. We will process your request within 30 days.

Local data and game progress

Certain game data — including coin balance, daily bonus timers, solved puzzle statistics, and ad cooldowns — is stored exclusively in the local storage of your device (SharedPreferences). This data is not backed up to any server and cannot be restored by the Service Provider. Clearing the Application's data via Android system settings ("Clear Data") will result in permanent and irreversible loss of this locally stored progress. The Service Provider bears no responsibility for data loss resulting from this action.

8. Security

All data transmitted by third-party SDKs is encrypted in transit (HTTPS/TLS). Local data on your device is protected by your device's built-in security mechanisms. We strongly advise against jailbreaking or rooting your device, as this may compromise security and affect Application functionality.

While we and our SDK providers take reasonable measures to protect data, no system is entirely immune to security incidents.

9. Changes to this Privacy Policy

We may update this Privacy Policy from time to time. Changes will be published on this page with an updated effective date. We encourage you to review this page periodically. Continued use of the Application after changes are posted constitutes acknowledgment of the updated policy.

10. Contact