Last updated: 13 June 2026
This Privacy Policy explains how the mobile game Hashi (the “App”) handles your information. The App is a Hashiwokakero bridge puzzle game available on Android and iOS.
The data controller responsible for your information is:
Dmitriy Zharkov, an individual developer based in Germany
Contact: dimitrij.zharkov@gmail.com
We aim to collect as little personal data as possible. Where we do collect data that requires your consent, we ask for it through an in-app consent prompt and do not collect that data until you agree.
If you consent, we use Google Firebase Analytics / Google Analytics to understand how the App is used so we can improve it. This may include:
usage events — for example, puzzles started and completed, features used, screens viewed, and session activity;
technical and device information — device model, operating system, App version, language, and approximate (coarse) region.
Analytics collection is off by default and only begins after you consent. Analytics data is processed by Google and may be exported to Google BigQuery for analysis. We store and process this data in the European Union.
The App shows advertising provided by Google AdMob to support its development.
If you consent to personalized advertising, ads may be tailored using advertising identifiers and related data.
If you do not consent, you will still see ads, but they will be non-personalized (contextual) and not based on your personal data.
Advertising is delivered and processed by Google and its advertising partners, who may process device identifiers. For details on how Google uses data, see Google’s information on how Google uses data from sites or apps that use its services.
The App offers optional competitive tournaments with leaderboards. To run these, we use Supabase (hosted in the European Union) to store:
an anonymous identifier created for you automatically — it is not linked to your name, email, or any real-world identity, and we do not ask you to create an account;
an automatically generated display name (for example, “dinosaur1512”);
your tournament results and completion times.
Please note: your generated display name and your times are shown to other players on public tournament leaderboards. Do not treat the display name as private.
Your game progress, statistics, streaks, rank, and settings are stored locally on your device. This data stays on your device and is used to run the game.
Where the GDPR applies, we rely on:
Consent (Art. 6(1)(a) GDPR) for analytics and personalized advertising;
Legitimate interests / performance of a service (Art. 6(1)(b)/(f) GDPR) to operate the App and its anonymous tournament features, and to show non-personalized advertising.
You can withdraw your consent at any time within the App under Settings → Manage ad consent. Withdrawing consent does not affect the lawfulness of processing carried out before withdrawal.
We use the following service providers, which process data on our behalf:
Google (Firebase, Google Analytics, AdMob, BigQuery) — see the Google Privacy Policy.
Supabase — used to host anonymous tournament data in the European Union.
We do not sell your personal data.
Analytics data (Google) and tournament data (Supabase) are processed in the European Union. We retain data only as long as needed for the purposes described above, after which it is deleted or anonymized. Analytics data is subject to Google’s retention settings.
Where the GDPR applies, you have the right to access, correct, delete, or restrict processing of your personal data, to object to processing, to data portability, and to withdraw consent at any time. Because tournament data is tied only to an anonymous identifier, it is generally not linked to your real-world identity. To exercise your rights or ask a question, contact us at dimitrij.zharkov@gmail.com. You also have the right to lodge a complaint with a data protection supervisory authority.
The App is not directed at children under the age of 16, and we do not knowingly collect personal data from children under 16. If you believe a child has provided us with personal data, please contact us and we will delete it.
We may update this Privacy Policy from time to time. The “Last updated” date at the top reflects the latest version. Significant changes will be communicated within the App where appropriate.
If you have any questions about this Privacy Policy or your data, contact:
Dmitriy Zharkov
dimitrij.zharkov@gmail.com