sDoku Privacy Policy

If you connect a Sapplify Account

If you sign in to sDoku with a Sapplify Account to use the league tables, the Sapplify Account Privacy Policy and Sapplify Account Terms of Service additionally apply to your use of account-related features (sign-in, your profile, and the byline/display name shared across Sapplify apps).

1. Introduction

Welcome to the Privacy Policy for sDoku ("we", "us", or "our"). sDoku is a sudoku app printed like a vintage newspaper: one daily puzzle for every reader, an archive of fresh puzzles graded by the techniques a human actually needs, and press cuttings you collect as you solve. This Privacy Policy describes how we handle your data while you play, with complete control kept in your hands.

sDoku operates on a local-first principle by default: your puzzles, progress, statistics, and cuttings are stored on your device. The only feature that sends anything about your play to our servers is the optional league tables, and only when you have signed in and hold a Press Pass. This Privacy Policy describes that default, local behavior and the limited league-tables exception.

Please read this policy carefully. By using sDoku, you acknowledge that you have read and understood this Privacy Policy.

Data Controller

The data controller responsible for your personal data is:

Anthony Eli Rasch - sapplify
PO Box 004
91501 Nove Mesto nad Vahom
Slovakia
ICO: 56665032

Email: contact@sapplify.com
Privacy inquiries: privacy@sapplify.com

Data Protection Officer

Sapplify operates at a scale that does not require the designation of a Data Protection Officer under Article 37 GDPR. For any data protection inquiry, contact privacy@sapplify.com.

2. Definitions

To help you understand this Privacy Policy, we define the following terms:

• Personal Data: Any information relating to an identified or identifiable person.
• Local Storage: Data stored only on your device, not transmitted to external servers.
• Game Data: The puzzles you play, your progress and completed grids, solve times, statistics, streaks, and press cuttings. By default this is stored only on your device.
• Sapplify Account: An optional sign-in identity that lets you use the same account across all Sapplify apps. In sDoku it is used only for the league tables.
• Byline: The display name you choose to appear next to your times on the league tables. It is part of your Sapplify Account profile and is shared across Sapplify apps. Bylines are not required to be unique.
• League Tables: Optional public leaderboards that rank subscribers' solve times and points. Reading the tables is free for everyone; filing your own times requires signing in and holding a Press Pass.
• Press Pass: Access unlocked by a paid purchase from the Press Counter — either a recurring subscription or the one-time Patron edition. A Press Pass unlocks league-table filing and the subscriber paper stocks.
• Processing: Any operation performed on personal data, including collection, storage, use, and deletion.

3. Data Collection

sDoku is a privacy-focused app. By default, all your game data is stored on your device and is not transmitted to external servers.

Game Data (stored on your device)

The app stores the following on your device as you play:

• Puzzle progress: The grids you are working on, your entered digits, pencil marks, and whether a puzzle is solved
• Solve records: Your solve times, hints used, mistakes made, and difficulty for puzzles you complete
• Statistics and streaks: Aggregate play statistics and your daily reading streak
• Press cuttings: The achievements you have earned and their printing tier
• Preferences: Your chosen paper stock, entry mode, language, and other settings

Sapplify Account Data (only if you sign in)

If you sign in to use the league tables, your Sapplify Account holds your email address (or the identifier from Sign in with Apple / Sign in with Google) and your chosen byline. Account data on our servers is governed by the Sapplify Account Privacy Policy.

League Solve Records (only if you sign in, hold a Press Pass, and file)

When you file a solve to the league tables, a record is sent to our servers containing: the puzzle identifier, difficulty, your solve time in seconds, the number of hints and mistakes, the points earned, and a timestamp, linked to your account. Your byline is shown alongside your times on the public tables. See Section 5 for full details.

Diagnostic Data

To keep sDoku reliable, we automatically collect crash reports and basic performance data through our own in-house analytics (not a third-party service). This includes:

• App version and platform
• An anonymous device identifier generated at install, and a session identifier
• Event names such as puzzle solved, app opened, or purchase completed
• If a crash occurs: the error type, message, and a truncated stack trace

Optional Feedback Data

If you choose to submit feedback through the app, we collect:

• Your feedback message and type (bug report, feature request, general)
• App version and device information (model, operating system)
• Your locale/language
• Email address (optional, only if you provide it for follow-up)

What We DO NOT Collect

• We DO NOT collect your name, address, or personal identification documents (other than the email address tied to a Sapplify Account, if you create one)
• We DO NOT collect GPS location or movement data
• We DO NOT access your photo library, contacts, camera, microphone, or other personal files
• We DO NOT use third-party analytics or advertising SDKs (no Google Analytics, Firebase Analytics, Facebook Ads, or similar)
• We DO NOT display advertisements or use advertising networks
• We DO NOT collect health data, medical information, or biometric data
• We DO NOT track you across devices or apps

4. Legal Basis for Processing

Under the General Data Protection Regulation (GDPR) and applicable data protection laws, we process your personal data based on the following legal grounds:

Contract Performance (Article 6(1)(b) GDPR)

We process data when necessary to provide you with the sDoku service:

• Storing your puzzle progress, statistics, and cuttings locally
• Managing your app settings and preferences
• Verifying your Press Pass status
• Operating the league tables you choose to file to, including displaying your byline and times

Consent (Article 6(1)(a) GDPR)

For the league tables, we rely on your consent: you provide it by signing in, choosing a byline, and actively filing a solve. You can withdraw it at any time by ceasing to file, changing your byline, or deleting your Sapplify Account.

Legitimate Interest (Article 6(1)(f) GDPR)

We process limited data based on our legitimate interests:

• Reliability: Collecting diagnostic (crash and performance) data to find and fix bugs and keep the app working.
• Feedback processing: When you voluntarily submit feedback, processing it to improve our app and respond to your inquiries.
• Fair play and moderation: Screening bylines and, where necessary, removing bylines or league entries that are abusive or that violate our Terms.

You have the right to object to processing based on legitimate interests. See Section 14 for how to exercise this right.

Legal Obligations (Article 6(1)(c) GDPR)

We may process data when required by law, such as responding to valid legal requests from authorities.

5. The League Tables

The league tables are optional public leaderboards. This section explains exactly what data is involved and who can see it.

Reading is free; filing needs a Press Pass

• Reading the tables is free for everyone and does not require an account.
• Filing your own times requires you to sign in with a Sapplify Account and hold a Press Pass. Without both, nothing about your play is sent to the tables.

What is filed

When you file a solve, we send to our servers (Supabase, EU region — Frankfurt): the puzzle identifier, whether it is the daily edition and its date, the difficulty, your solve time in seconds, the number of hints and mistakes, the points earned, and a timestamp. Each record is linked to your Sapplify Account.

What other readers can see

The public tables show your byline and your times/points only. Today's table ranks hint-free solves of the daily edition, fastest first; weekly and monthly tables rank points. Other readers cannot see your account, your email, your device, or any puzzle you have not filed. Your individual solve records are private to your account (protected by row-level security); only the ranked byline-and-time summary is exposed through the leaderboard.

Your byline

Your byline is a display name you choose. It is part of your Sapplify Account profile and is shared across Sapplify apps. Bylines are not required to be unique, so more than one reader may share a byline; your own entries are marked as yours in the app. Please do not put personal information you would not want shown publicly into your byline.

The Correspondents

Before real subscribers fill the tables, the paper's own correspondents appear on them as a clearly-marked cold-start. They are fictional entries generated by the app, not real people, and they make room as real subscribers file their times. No personal data is involved in the correspondents.

6. Data Transmission

sDoku is designed as a local-first app. There are limited circumstances where data may be transmitted to our servers:

League Filing (User-Initiated, if signed in with a Press Pass)

If you have signed in and hold a Press Pass, the solve records described in Section 5 are transmitted to our servers in Supabase's EU region (Frankfurt) so your times can appear on the league tables. Your account and byline are handled as described in the Sapplify Account Privacy Policy.

Diagnostic Data (Automatic)

Crash reports and basic performance events (described in Section 3) are sent automatically to our own analytics backend, hosted in Frankfurt, Germany (EU). This is a first-party service we operate ourselves — it is never shared with a third-party analytics or advertising company.

Feedback Submission (User-Initiated)

When you voluntarily submit feedback through the app, your message and category, the app version, your device model and operating system version, your locale, and your email address (only if you choose to provide it) are sent to our server.

Server location: Frankfurt, Germany (EU)
Endpoint: api.sapplify.com
Encryption: All transmissions use HTTPS/TLS encryption

What Is NEVER Transmitted Without Your Action

Unless you sign in and file to the league tables, none of the following ever leaves your device:

• Your puzzle grids and progress
• Your statistics and streaks
• Your press cuttings
• Your preferences

The anonymous diagnostic events described in Section 3 are the only automatic transmission, and they never include your game data as content.

Offline Functionality

The full game works offline. Solves you complete offline while holding a Press Pass are queued locally and filed to the league tables when connectivity returns.

7. App Permissions

sDoku requests only the permissions necessary to function:

Required Permissions

• Internet Access: Used for:
  • League-table filing and reading (only if you use that feature)
  • Sapplify Account sign-in (only if you sign in)
  • In-app purchase verification through app stores
  • Submitting feedback (user-initiated only)
  • Sending anonymous diagnostic (crash/performance) data
  • Opening links to our website, support pages, or privacy policy
  • Checking for app updates through app stores
• Billing Permission (Android): Required for in-app purchases through Google Play

Optional Permissions

• Notification Access: For daily puzzle reminders, only if you enable them

Permissions We DO NOT Request

• Camera
• Microphone
• Photo library
• Contact list access
• Location services (GPS)
• Calendar access
• Health app integration (HealthKit/Google Fit)
• Background location or tracking

8. Purchases & Payments

sDoku is free to play. The optional purchases live at the Press Counter:

• Press Pass subscription (recurring, monthly or yearly): unlocks filing your times to the league tables and the subscriber paper stocks (Sepia and Archival).
• Patron edition (one-time purchase): the same unlocks as a subscription, held forever, with no recurring billing.
• Tips (one-time): the coffee, ink, and crate tips are voluntary support for the presses. They unlock nothing and grant no features.

The full game — the daily puzzle, the archive, statistics, and press cuttings — is free and needs no purchase and no account.

Payment Processing

All payments are processed exclusively through official app stores:

• Apple App Store: For iOS users - Apple Privacy Policy
• Google Play Store: For Android users - Google Privacy Policy

What We Track

• Your Press Pass status (none, subscriber, or patron)
• The product identifier of the pass you hold, mirrored to your account so a pass follows you to a new device

What We DO NOT Track

• Credit card or payment method details
• Billing address or name
• Purchase receipts or amounts

We never see or store your payment details. All payment processing, refunds, and subscription management is handled entirely by the respective app store.

9. Data Sharing

We are committed to keeping your data private. Here's our complete data sharing policy:

We DO NOT Sell or Broker Your Data

• We DO NOT sell your data to anyone
• We DO NOT share data with advertisers or marketing companies
• We DO NOT share data with data brokers or analytics firms
• We DO NOT share data with social media platforms

The One Thing That Is Public By Your Choice

If you file to the league tables, your byline and your times/points are shown publicly on those tables to anyone reading them. This is the entire purpose of the feature and happens only because you signed in, held a Press Pass, and filed. Nothing else about you is made public.

Service Providers

If you sign in or file to the league tables, your account and league data are processed by the sub-processors listed in the Sapplify Account Privacy Policy §6 (primarily Supabase for the database and authentication, in the EU).

Legal Requirements

We may disclose information if required by law, such as in response to a valid court order or government request. We will notify you of such requests when legally permitted. We have never received such a request to date.

10. Third-Party Services

sDoku minimizes third-party dependencies to protect your privacy. The following services may be involved when you use the app:

App Distribution & Purchases

• Apple App Store: App distribution and in-app purchases for iOS - Privacy Policy
• Google Play Store: App distribution and in-app purchases for Android - Privacy Policy

First-Party Services (Our Own Servers)

• Sapplify API: Our own server (Frankfurt, Germany) for processing user-submitted feedback
• Sapplify Analytics: Our own in-house crash and performance reporting (Frankfurt, Germany) — not a third-party analytics provider

Sapplify Account and League Tables (if you sign in)

If you sign in or file to the league tables, additional sub-processors are involved (Supabase for the database and authentication, and Resend for transactional email). The full list, with roles, locations, and links, is in the Sapplify Account Privacy Policy §6. Sign in with Apple and Sign in with Google, if you choose them, are governed by Apple's and Google's own privacy policies.

What We DO NOT Use

• No Google Analytics or any third-party analytics service
• No Firebase Analytics or Crashlytics
• No advertising networks (Facebook Ads, Google Ads, etc.)
• No social media SDKs or integrations
• No user tracking or behavioral analytics

Fonts

The app includes fonts locally bundled within the app. No external font loading or requests are made during app use.

11. Data Security

We implement security measures to protect your data:

Local Data Security

Device Cloud Backup Disclosure

Independently of sDoku, your local game data may be included in your device's native cloud backup services (iCloud Backup on iOS, Google backup on Android) if you have them enabled. Apple and Google encrypt these backups, but your data would be stored on their servers. You can manage these in your device settings. We are not responsible for the security or privacy practices of third-party cloud backup providers.

League and Account Transmission Security

• All network communications use HTTPS/TLS encryption
• Server located in Frankfurt, Germany (EU jurisdiction)
• League and account data are encrypted in transit (TLS) and at rest. This is not end-to-end encryption; Sapplify-side service-role access could in principle read the stored records (we access them only as needed to operate the service). See the Sapplify Account Privacy Policy §9 for the full disclosure

Your Responsibility

To maximize security, we recommend you enable device lock screen protection, keep your operating system and the app updated, and avoid using sDoku on shared or public devices while signed in.

12. Data Retention & Deletion

Game Data Retention

• All local game data (puzzles, progress, statistics, streaks, cuttings, settings) is stored on your device indefinitely until you delete it
• For local data, we have no access and cannot delete it remotely; you have complete control

League Solve Records

• Solve records you file are retained on our servers (Supabase, EU) while your Sapplify Account exists, so the tables can rank them
• They are deleted when you delete your Sapplify Account

Diagnostic Data Retention

• Crash and performance data is retained only as long as needed to diagnose issues and improve app reliability

Feedback Data Retention

• Submitted feedback is retained on our servers for up to 2 years and used to improve the app and respond to inquiries
• You can request deletion of feedback data by contacting us

How to Delete Your Data

Delete Local Data

Uninstalling the app removes all local game data from your device. You can also reset app data from your device's app settings.

Delete Your Sapplify Account (if you created one)

Deleting your Sapplify Account from inside the app immediately hard-deletes all server-side account data, including your filed league solve records. See the Sapplify Account Privacy Policy §13.

Delete Feedback Data

Email privacy@sapplify.com to request deletion of any feedback you have submitted.

13. Your Rights

You have comprehensive rights over your personal data:

General Rights (All Users)

• Access: View all your progress, statistics, and cuttings within the app at any time
• Correction: Change your settings and your byline directly in the app
• Deletion: Delete local data by uninstalling; delete server-side data by deleting your Sapplify Account
• Withdraw Consent: Stop filing to the league tables at any time

GDPR Rights (EU/EEA Users)

Under the General Data Protection Regulation, you have the following rights:

• Right of Access (Art. 15): Request confirmation of what personal data we process
• Right to Rectification (Art. 16): Request correction of inaccurate data
• Right to Erasure (Art. 17): Request deletion of your personal data ("right to be forgotten")
• Right to Restriction (Art. 18): Request limitation of processing
• Right to Data Portability (Art. 20): Receive your data in a machine-readable format
• Right to Object (Art. 21): Object to processing based on legitimate interests
• Right to Withdraw Consent (Art. 7): Withdraw consent at any time
• Right to Lodge a Complaint: File a complaint with your local data protection authority

CCPA/CPRA Rights (California Users)

California residents have additional rights under the California Consumer Privacy Act and California Privacy Rights Act, including the right to know, delete, correct, and opt out of the sale or sharing of personal information.

We do not sell or share your personal information. We do not "sell" your data as defined by the CCPA, nor do we "share" it for cross-contextual behavioral advertising. We have no advertising in our app and do not monetize your data.

UK GDPR Rights (United Kingdom Users)

For users in the United Kingdom, all references to GDPR in this policy include the UK GDPR as retained in UK law. You may lodge complaints with the Information Commissioner's Office (ICO) at ico.org.uk.

LGPD Rights (Brazil Users)

Users in Brazil have rights under the Lei Geral de Proteção de Dados (LGPD) similar to the GDPR rights above. For questions about LGPD compliance, contact us at privacy@sapplify.com.

Exercising Your Rights

For local data, you can exercise most rights directly within the app or by uninstalling. For server-side account and league data, delete your Sapplify Account from inside the app, or contact privacy@sapplify.com. We will respond to verified requests within 30 days (or 45 days for complex requests, with notification).

14. Children's Privacy

sDoku is intended for users who are at least 13 years old. We do not knowingly collect personal information from children under 13. In some EU/EEA member states, the minimum age for consenting to data processing may be higher (up to 16 years) under GDPR Article 8; that higher age applies where required by local law.

• If you use sDoku without a Sapplify Account, all game data is stored only on your device and we have no access to it or to your age
• If you sign in with a Sapplify Account, you confirm that you meet the minimum age requirement in your jurisdiction

Parental Notice

If you are a parent or guardian and discover your child under 13 has been using sDoku:

• If the child has not signed in, all game data is stored only on their device and we have no access to it; uninstalling the app removes it
• If the child created a Sapplify Account, delete the account from inside the app to immediately hard-delete all server-side data; see the Sapplify Account Privacy Policy §13

If you believe your child under 13 has submitted feedback through the app, please contact us at privacy@sapplify.com and we will delete any such data promptly.

15. International Users

sDoku is available to users worldwide.

App Language

The sDoku app interface is currently available in English. Sign-in and account screens (shared across the Sapplify suite) support 18 languages, matching your Sapplify Account. This website, including this policy, is also available in multiple languages.

Local-only data (default)

By default, all game data is stored on your device. In that mode there are no cross-border data transfers.

Account and League Data (if you sign in)

If you sign in or file to the league tables, your data is transferred to and stored in Supabase's EU region (Frankfurt). See the Sapplify Account Privacy Policy §7 for full residency and international-transfer details.

Feedback and Diagnostic Data

If you choose to submit feedback, or when the app automatically sends diagnostic data, it is processed on servers located in Frankfurt, Germany (European Union). EU users' data remains within the EU; non-EU users' data is transferred to the EU, which maintains high data protection standards under GDPR.

16. Data Breach Notification

By default, sDoku does not send your game data to any server, so there is no server-side breach surface for that data. This section covers the cases where server-side data does exist.

Local data on your device

Your puzzles, progress, statistics, and cuttings are stored locally. They are not affected by any server-side incident on our side. To protect them, keep your device locked and your operating system patched.

Voluntary feedback and diagnostic data

Feedback you submit, and the automatic diagnostic data described in Section 3, are sent to our servers (Frankfurt, EU). In the unlikely event of a security incident there, we will investigate the scope, notify the Slovak Office for Personal Data Protection within 72 hours under GDPR Article 33, and notify you without undue delay under Article 34 if the breach poses a high risk to your rights.

Account and League Data (if you sign in)

If you have signed in and filed to the league tables, your account and solve records are held on our servers (Supabase, EU region). Breach notification for that data follows the same 72-hour authority notification and high-risk user-notification process, described in the Sapplify Account Privacy Policy §10.

To date, we have not experienced a personal data breach affecting sDoku users.

17. Changes to This Privacy Policy

We may update this Privacy Policy to reflect changes in our practices, add new features, or comply with legal requirements.

How We Notify You

When we make material changes, we will update the "Last updated" date at the top of this policy and, where required, prompt you in the app. For account-related documents, re-acceptance may be required and is tracked within the app.

Your Continued Use

Your continued use of sDoku after changes are posted constitutes acceptance of the updated Privacy Policy. If you do not agree with the changes, you should stop using the app and delete your data.

We encourage you to review this Privacy Policy periodically.

18. Governing Law

This Privacy Policy and any disputes arising from it are governed by the laws of the Slovak Republic, without regard to conflict of law principles.

EU Users - Supervisory Authority

If you are located in the European Union, you have the right to lodge a complaint with your local data protection supervisory authority if you believe we have violated your data protection rights.

As we are based in Slovakia, our lead supervisory authority is:

Urad na ochranu osobnych udajov Slovenskej republiky
(Office for Personal Data Protection of the Slovak Republic)
Hranicna 12
820 07 Bratislava 27
Slovak Republic
Website: dataprotection.gov.sk
Email: statny.dozor@pdp.gov.sk

Dispute Resolution

We encourage you to contact us first at privacy@sapplify.com to resolve any concerns or disputes. We are committed to working with you to reach a fair resolution.

19. Contact Us

If you have any questions, concerns, or requests regarding this Privacy Policy or your data, please contact us:

General Inquiries:
contact@sapplify.com

Privacy & Data Protection:
privacy@sapplify.com

Postal Address:
Anthony Eli Rasch - sapplify
PO Box 004
91501 Nove Mesto nad Vahom
Slovakia

Response Time

We are committed to addressing your privacy concerns and will respond to your inquiry within 30 days. For complex requests, we may extend this by an additional 60 days with notification.