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Privacy Notice

Sudoku Master – Brain Game & Logic Puzzles
Operated by Vertex Studios Ltd
Last updated: June 13, 2026
Contact: contact@vertexstudios.online

1. Overview

This Privacy Notice describes how Vertex Studios Ltd (“we,” “us,” or “our”) handles information when you use Sudoku Master and related support services.

Sudoku Master is a single-player and friend-versus-friend Sudoku game with campaign levels, daily challenges, an interactive Sudoku School, and battle modes. You can play the entire game without creating an account. We have built Sudoku Master to keep your data on your device wherever possible, and to collect only what is needed to deliver paid features, optional online play, and a free, ad-supported version.

2. Summary of Key Points

  • No account, login, email, or password is required to play.
  • Your puzzle progress, statistics, achievements, streaks, and settings are stored locally on your device.
  • The free version shows ads through Google AdMob. Purchasing Lifetime Access or a Pro subscription removes all ads.
  • On Apple devices we use App Tracking Transparency: advertising-related tracking only happens with your permission, and you can decline.
  • Optional online features (Friend Duel and the global “TOP n%” ranking) send a small amount of game data to our backend, which is hosted by Supabase. Play is anonymous — identified only by a display name you choose and a random identifier generated on your device.
  • Payments are handled by Apple through the App Store. We do not see your card details.
  • We do not collect contacts, precise location, photos, microphone audio, or health data. No sale of personal data.

3. Table of Contents

  1. Overview
  2. Summary of Key Points
  3. Table of Contents
  4. What Information Do We Collect?
  5. How Do We Use Your Information?
  6. What Legal Bases Do We Rely On?
  7. When and With Whom Do We Share Personal Information?
  8. Advertising and Your Choices
  9. Third-Party Websites and External Links
  10. Cookies and Tracking Technologies
  11. International Data Transfers
  12. How Long Do We Keep Your Information?
  13. How Do We Keep Your Information Safe?
  14. Do We Collect Information From Minors?
  15. What Are Your Privacy Rights?
  16. Controls for Do-Not-Track Features
  17. California Privacy Rights
  18. Do We Make Updates to This Notice?
  19. How Can You Contact Us?
  20. Additional Apple App Privacy Disclosures

4. What Information Do We Collect?

A) Information stored only on your device

  • Puzzle progress and saved games, level completion, and mistakes.
  • Statistics and achievements (win rates, best times, perfect games, streaks, brain points).
  • Daily Challenge calendar, Battle progress, tickets, and season state.
  • Onboarding answers (such as your self-reported skill level), preferences, sound/haptics, and light/dark mode.

This content is kept in local storage on your device. It is not sent to our servers and we do not have access to it.

B) Friend Duel (online multiplayer) data

When you choose to play a Friend Duel, the App connects to our matchmaking backend (hosted by Supabase) so two devices can race on the same puzzle. For an active match we process:

  • A 6-character room code you share with your friend.
  • A display name you choose (which defaults to “Solver” and may be a nickname).
  • The puzzle seed and difficulty, so both phones generate the identical board.
  • Your live board progress (a completion percentage) and your mistake count.
  • The match status and who won or forfeited.

Friend Duel is played anonymously. There is no login, and we do not attach this data to your name, email, or Apple ID. You only generate this data if you start or join a duel.

C) Global ranking (“TOP n%”) data

To power the real percentile badges shown on your stats screen, after a win the App can send aggregate totals to the same backend: your games won, perfect wins, best streak, and total score, together with a display name and a random identifier generated on your device. We use this only to compute your rank relative to other players. It is not linked to your real-world identity.

D) Purchases and subscriptions

  • Purchase status and transaction/receipt data for Lifetime Access (a one-time purchase) and Pro Weekly / Pro Yearly subscriptions, used to unlock and restore paid features.

Payment processing and subscription management are handled by Apple through the App Store using StoreKit. We do not receive or store your payment card information. We only receive the minimum information needed to confirm whether a purchase or subscription is valid and active.

E) Advertising (free version)

The free version of Sudoku Master displays ads — a banner during play and an optional rewarded ad you can watch for a “second chance” after running out of mistakes. Ads are provided by Google AdMob. To serve and measure ads, Google may process information such as a device advertising identifier, approximate (coarse, non-precise) location derived from your IP address, device and app information, and ad interaction data, in accordance with Google’s policies.

On Apple devices, any advertising-related tracking is governed by App Tracking Transparency (see Section 8). If you purchase Lifetime Access or a Pro subscription, ads are removed and the advertising SDK no longer serves ads to you.

F) Aggregate app performance analytics

We use the aggregate, non-identifying analytics that Apple makes available to developers through App Store Connect (such as install counts, crash reports, and performance metrics). These help us monitor stability and improve performance. Apple controls this data; we do not receive personally identifiable information from it.

G) Support correspondence

If you email us for support, we receive your email address and whatever information you choose to include in your message.

H) What we do not collect

We do not collect your contacts, precise location, photos, microphone audio, or health data. We do not require an account and do not collect your name, email, or password to play. We do not build advertising profiles ourselves or sell personal data.

5. How Do We Use Your Information?

We use the limited information described above only to:

  • Run online features you choose to use (Friend Duel matchmaking and global ranking).
  • Validate purchases and subscriptions and unlock or restore paid features.
  • Display and measure ads in the free version.
  • Monitor aggregate app performance and reliability through Apple-provided analytics.
  • Respond to your support requests.
  • Comply with legal and regulatory requirements, and prevent fraud and abuse.

6. What Legal Bases Do We Rely On?

Where required by applicable law, we rely on one or more legal bases to process personal data, including:

  • Performance of a contract (to deliver and validate the paid features you purchase and the online matches you start).
  • Legitimate interests (service reliability, security, fraud prevention, and basic measurement).
  • Consent, where applicable under local law (including for personalized advertising and tracking, where you can grant or decline permission).
  • Legal obligations (compliance and enforcement requirements).

7. When and With Whom Do We Share Personal Information?

We share information only as needed to operate Sudoku Master:

  • Apple: processes App Store billing and payments and provides aggregate App Store Connect analytics.
  • Supabase: hosts the backend that stores Friend Duel match data and aggregate ranking stats while online features are in use.
  • Google AdMob: serves and measures ads in the free version, as described in Section 4(E) and Section 8.
  • Legal requests: we may disclose data when required by law, legal process, or enforceable government request.

We do not sell your personal information, and we do not share it with data brokers or any party not listed above. We require processors handling data on our behalf to provide safeguards including confidentiality, secure transfer, access controls, and purpose-limited processing.

8. Advertising and Your Choices

The free version is supported by ads from Google AdMob. On Apple devices, the App uses Apple’s App Tracking Transparency framework: before any tracking that relies on the device advertising identifier, you are asked for permission. If you decline (or have “Allow Apps to Request to Track” turned off in Settings), you may still see ads, but they will be non-personalized.

You can reset or limit your advertising identifier in your device’s privacy settings. The most reliable way to remove ads entirely is to purchase Lifetime Access or a Pro subscription. To learn how Google uses information from apps that use its services, see Google’s privacy and advertising policies.

9. Third-Party Websites and External Links

Sudoku Master may include links to third-party websites or services (for example, Apple Support or Google). We are not responsible for the privacy practices of services not operated by Vertex Studios Ltd. Review those third-party privacy notices before providing personal data.

10. Cookies and Tracking Technologies

Sudoku Master is a mobile app and does not use browser cookies. The advertising SDK in the free version may use device identifiers and similar technologies for ad delivery and measurement, subject to your App Tracking Transparency choice (see Section 8). The paid versions do not serve ads.

11. International Data Transfers

The limited data we process (payments via Apple, online features via Supabase, and advertising via Google) may be processed in countries outside your region through these providers. When cross-border transfers occur, we and our providers rely on appropriate safeguards and contractual protections under applicable law.

12. How Long Do We Keep Your Information?

  • Game progress, statistics, and settings: stored locally on your device; removed when you reset progress or uninstall the app.
  • Friend Duel match data: short-lived; matches are intended to be cleared after play and may be deleted on a routine basis.
  • Aggregate ranking stats: retained while the ranking feature operates so percentile calculations remain accurate.
  • Purchase records: retained as needed to maintain and audit paid access.
  • Support records: retained as needed to resolve requests and maintain support history.

13. How Do We Keep Your Information Safe?

We use reasonable organizational and technical safeguards, including HTTPS/TLS encryption in transit for data we transmit, restricted access controls, and the service-level security controls provided by Apple, Supabase, and Google. No method of transmission or storage is completely secure.

14. Do We Collect Information From Minors?

Sudoku Master is not directed to children under 13, or the applicable minimum age in your region, and we do not knowingly collect personal data from children. The free version contains third-party advertising. If you believe a child has provided us with personal data, contact us so we can take appropriate action.

15. What Are Your Privacy Rights?

Depending on your location, you may have rights to access, correct, delete, restrict processing of, or request a copy of your personal data, and to object to certain processing or withdraw consent at any time.

Because your gameplay data is stored locally, you can remove it at any time by resetting progress in the App or uninstalling it. You can change your advertising permission at any time in your device settings. To exercise other rights, or to request deletion of online ranking or match data associated with your random identifier, contact us at contact@vertexstudios.online.

16. Controls for Do-Not-Track Features

As a mobile app, Sudoku Master does not respond to browser Do-Not-Track signals. Your primary control over advertising tracking is the App Tracking Transparency prompt and your device privacy settings, described in Section 8.

17. California Privacy Rights

California residents may have specific rights regarding personal information under California law, including the right to request information about certain data disclosures and the right to request deletion or correction of personal information, subject to legal exceptions. We do not sell personal information.

To submit a California privacy request, contact us at contact@vertexstudios.online.

18. Do We Make Updates to This Notice?

We may update this Privacy Notice as laws or service features change. We will update the Last updated date when we post changes.

19. How Can You Contact Us?

If you have questions about this Privacy Notice or your data, contact:

Vertex Studios Ltd
Email: contact@vertexstudios.online
Website: https://www.vertexstudios.online

20. Additional Apple App Privacy Disclosures

For App Store review clarity:

  • Data linked to user: purchase/subscription data, support email correspondence.
  • Data not linked to user: gameplay data kept on device; anonymous Friend Duel and ranking data identified only by a chosen display name and a random identifier; aggregate App Store Connect analytics provided by Apple.
  • Data used for tracking: in the free version, advertising identifiers may be used for tracking only if you grant App Tracking Transparency permission. The paid versions do not serve ads.
  • Data recipients: Apple (billing and platform analytics), Supabase (online features), and Google AdMob (advertising in the free version).
  • No sale of personal data.

Last updated: June 13, 2026