Effective Date: 11.08.2026
This privacy policy explains how Next10 collects, uses, stores, and protects your personal data when you use our app. We built Next10 to help you track your habits and goals, and we take your privacy seriously. Please read this policy carefully to understand your rights and how your data is handled.
The controller responsible for your personal data under the General Data Protection Regulation (GDPR) is:
Nazar Mishchenko
Email: nazar.mischenko13@gmail.com
For any questions about this privacy policy or to exercise your data protection rights (see Section 10), you can contact the above email address at any time.
Since Next10 is currently operated by an individual rather than a registered company, no separate Data Protection Officer (DPO) has been appointed — this is not legally required at your current scale under GDPR (a DPO is mandatory only for large-scale systematic monitoring or large-scale special-category data processing, which doesn't apply here).
Collected via Firebase Authentication when you register:
Purpose: to create and secure your account, and to verify your identity when you sign in. Your email and password are processed exclusively by Firebase Authentication and never reach our Firestore database.
Visible to other users (to friends, or to any user if your profile is not set to private) — stored at users/{uid}:
Purpose: to let you build a public profile, be found by other users, and show your progress to friends without exposing what your goals or habits actually are.
Stored at users/{uid}/appdata/main — never visible to any other user, including friends. This data exists solely so your habits and goals are preserved and synced if you switch devices:
Purpose: to enable cross-device sync, so that if you switch phones or reinstall the app, all of your habit and goal data is restored exactly as you left it.
Purpose: to power the friends and social features of the app.
Vacation mode dates and app language preference stay on your device only.
Habit and goal titles are free text you choose yourself. If you voluntarily include sensitive information in these fields (e.g., referencing a health condition or medication), it is stored privately as described in 2.3 and is never shown to other users. We do not analyze or process this content for its meaning.
| Purpose | Data Used | Legal Basis |
|---|---|---|
| Creating and securing your account | Auth data (2.1) | Contract necessity (Art. 6(1)(b) GDPR) |
| Verifying subscription/payment status | Account ID and subscription status, processed via Apple's In-App Purchase system, Google Play Billing, and/or a third-party subscription platform (see Section 4 for current sub-processors) | Contract necessity (Art. 6(1)(b) GDPR) |
| Syncing your habits and goals across devices | Private app data (2.3) | Contract necessity (Art. 6(1)(b) GDPR) |
| Public profile, friend search, and social features | Public profile & friends data (2.2, 2.4) | Contract necessity (Art. 6(1)(b) GDPR) |
| Leaderboard / percentile ranking | Computed completion statistics (2.2) | Contract necessity (Art. 6(1)(b) GDPR) — advertised as a built-in feature of the app |
We use the following service providers to operate Next10. Each processes personal data only on our instructions and is bound by data processing agreements:
| Sub-processor | What They Process | Location |
|---|---|---|
| Google Firebase (Firestore) | Public profile, private app data, friends/social data | EU (eur3 — Belgium/Netherlands) |
| Google Firebase (Authentication) | Email, name, sign-in credentials | Global/US, transferred under the EU-U.S. Data Privacy Framework |
| Google (Google Sign-In) | Google account email and name, at your choice — see Google's Privacy Policy | Governed by Google's own privacy policy |
| Apple (Sign in with Apple) | Apple ID email/relay email and name, at your choice — see Apple's Privacy Policy | Governed by Apple's own privacy policy |
| Apple In-App Purchase / Google Play Billing / third-party processor — TBD | Subscription status | TBD once selected |
Most of your data (public profile, private app data, friends/social data) is stored in Google Firebase's EU region (eur3, physically located in Belgium and the Netherlands) and does not leave the European Union.
However, authentication data (your email, name, and sign-in credentials) is processed by Firebase Authentication on infrastructure that may be located outside the EU, including in the United States. This transfer is carried out under the EU-U.S. Data Privacy Framework (DPF), the legal mechanism recognized by the European Commission for transfers of personal data from the EU to certified U.S. companies. Google LLC is certified under this framework.
If you sign in using Google or Apple, those providers may also process limited data outside the EU as part of their own authentication systems, governed by their respective privacy policies (see Section 4).
Unlike most of your data, some information in Next10 is visible to other people using the app. Here's exactly what is shown, to whom, and when:
We retain your data for as long as your account remains active, since it is necessary for the app's core functionality (sync, profile, leaderboard).
Deleting your account: You can delete your account at any time directly within the app. When you do:
Backups: Due to how our infrastructure provider (Google Firebase) operates, deleted data may persist briefly in backup systems before being permanently purged. This is standard across cloud infrastructure and does not mean your data remains accessible or in use — it is simply the technical process of full deletion propagating through backup layers.
Next10 is rated 16+ on the App Store. It is intended for users aged 16 and older. If you are younger than 16, please only use the app with the permission and supervision of a parent or guardian.
We do not have a technical way to verify a user's age beyond what Apple or Google's account systems require. If you are a parent or guardian and believe your child has used Next10 and provided personal data, you can contact us at nazar.mischenko13@gmail.com to request that the data be reviewed or deleted, using the account deletion process described in Section 7.
We do not use any user's data — regardless of age — for advertising or sale to third parties.
Next10 includes an always-on leaderboard feature that shows you your percentile rank compared to other users, based on weekly and monthly habit and goal completion rates.
To calculate this, our system compares the completion statistics described in Section 2.2 across all users. No nickname, profile photo, goal name, habit name, or any other identifying detail is included in this calculation's output or shown to any user through the leaderboard. You only see your own numeric percentile rank.
Because this feature is a core, advertised part of the app, it is processed under the same legal basis as the rest of the app's functionality (contract necessity, Art. 6(1)(b) GDPR) — see Section 3.
Under GDPR, you have the right to:
To exercise any of these rights, contact us at nazar.mischenko13@gmail.com.
We take reasonable technical and organizational measures to protect your data, including:
No method of electronic storage or transmission is 100% secure. While we work to protect your data, we cannot guarantee absolute security.
We may update this privacy policy from time to time, for example if we add new features, change service providers, or as required by law. If we make material changes — such as adding a new sub-processor or changing the purpose for which your data is used — we will update the "Effective Date" below and, where appropriate, notify you within the app.
We encourage you to review this policy periodically.
Effective Date: 11.08.2026