Curious Sheep — Privacy Policy

This policy covers Curious Sheep for Android, including reading and vocabulary practice, our hosted book library and optional account progress synchronization.

Who operates the app

Developer and data controller: NNOff (Oleg Neyman), Israel
Privacy contact: neymanoff@gmail.com
Last updated: 14 October 2026

Reading and vocabulary

Curious Sheep stores your saved words and examples, reading position, practice results, daily goals and preferences on your device. For signed-in accounts with cloud synchronization access, the app checks cloud progress when opening or returning to the app and queues changes for automatic upload when the app is backgrounded or you sign out. Authorized owner/tester accounts and accounts with a server-verified library subscription have this access; the “Without subscription” preview disables it. The app sends your profile name and English level, dictionary entries and examples, practice results, reading positions, daily progress and English foundation checkpoints to our authenticated server for storage in private Google Cloud Firestore. The data is associated with your Curious Sheep account identifier. Book files, pronunciation recordings, sign-in tokens and device appearance or voice preferences are not copied into the learning snapshot. You can continue using local reading and vocabulary without synchronization. Offline changes stay on the device until a network connection and authentication for the same account are available. Cloud confirmation is required before another device can restore the changes; uninstalling the app removes unsent local data. Guest and signed-in learning data are kept separately. Returning to another account restores that account’s separate local data. Guest history can be copied into a signed-in account only when its existing local and cloud learning history is empty; it is not merged into an account with existing history. If two devices have independent changes, the app preserves both versions and asks which to use. Learning data is not displayed in the application administration panel.

Signing out does not delete your local learning data. It becomes available again when you return to the same app account. Android backup and device-transfer features may copy eligible data according to your device settings. The app excludes its Firebase sign-in session files from these backups.

Google sign-in

If you choose Google sign-in, Google and Firebase Authentication process your authentication information. The app uses your account identifier, email and email verification state to identify your app account and show its sign-in state. The sign-in provider may also supply basic profile information, such as your display name and profile picture, to Firebase. The app does not ask for your Google password or access to your Gmail messages or contacts.

Firebase processes technical information, including IP addresses, user-agent information and the Firebase application identifier, for authentication, service operation and abuse prevention. Firebase says logged IP addresses are kept for a few weeks; other authentication information is kept until deletion is initiated, then removed from live and backup systems within 180 days. See Firebase privacy and retention information.

Why we use information

We use information to provide the features you request, keep accounts separate, secure sign-in and respond to support or privacy requests. Where European or UK data-protection law applies, our grounds are providing the requested service, legitimate interests in security and support, and compliance with applicable legal obligations. Where consent is required for optional processing, you can withdraw it. You can use guest reading without Google sign-in and revoke microphone permission in Android settings.

The demo has no advertising or advertising-tracking SDKs. We do not sell personal information or share it for cross-context behavioural advertising, and do not use it for automated decisions with legal or similarly significant effects.

Library subscriptions

Library subscriptions use Google Play Billing. Sign in to Curious Sheep before purchase; the app shows the account receiving access and Google's localized monthly or annual price. Google handles checkout and payment details. NNOff does not receive your payment-card details. The library subscription does not include future AI features.

To verify, restore and maintain access, our authenticated server sends the purchase token and application/product identifiers to the Google Play Developer API. Private Firestore records associate an obfuscated app-account identifier with the receipt, plan, status, expiry and verification time. Google Play sends status-change notifications through Google Cloud Pub/Sub to our server, including when the app is closed. The server checks the current Google status before updating access. Purchase tokens and account bindings are not public, are not part of synchronized learning snapshots, and are not sent to AI development or tutoring models.

Subscriptions renew automatically through Google Play. Manage or cancel renewal in Google Play; canceling renewal retains the confirmed term. Downloaded paid books can be read offline until the end of the term most recently confirmed by our server. Renewals need another online verification to extend that deadline. An offline device cannot detect an earlier refund or revocation until reconnection or its recorded deadline. Ending access does not erase book files, your saved words or reading progress.

Deleting your Curious Sheep account does not cancel a Google Play subscription or stop renewal. Cancel renewal separately in Google Play. Google retains its payment records under its own terms and privacy policies.

Microphone and audio

When you choose to record your pronunciation in the reader, the app requests microphone permission. The recording is saved in this app's private cache on your device so you can play it back. This reader recording is not uploaded to our server.

Starting a new reader recording replaces the previous recording for that local learner. Leaving the reader stops recording or playback but does not itself erase the cached file. Android may clear cached files; clearing the app's cache removes these recordings.

Book narration is bundled with the app or included in books that you choose to download from our library. Synthesized pronunciation uses the device's text-to-speech service and installed offline voices. Recording your own pronunciation is optional.

Sharing and updates

If you choose Share, Android lets you select another app to receive the prepared app image or book cover, invitation or book description, credits where required, and Google Play link. This prepared content does not include your saved words, account details or reading progress. The receiving service handles what you choose to send under its own policies.

The Play release checks update availability through Google Play and opens its app listing when you choose to update.

Offline translation

When a prepared reading translation is unavailable, you can request a Google ML Kit translation. Download the language pack over Wi-Fi first; translation then runs on your device. Source text and translated text are processed on-device, and this feature does not save machine translations into your dictionary or learning progress.

When network access is available, the Google SDK can communicate with Google for language models, configuration, diagnostics and usage analytics. Technical data can include device and app information, installation identifiers, performance and error events, input/output sizes and configured languages. ML Kit also uses Firebase Remote Config and Firebase Installations; configuration metadata can include country and language codes, time zone and software versions. See Google's ML Kit data disclosure and Firebase's SDK data disclosure. These service connections use HTTPS; offline translation does not mean the SDK never communicates with Google.

Using machine translation is optional. The app does not provide a separate switch to disable the SDK's technical diagnostics. These SDK records are separate from your local learning progress and your Firebase sign-in account; deleting that account does not itself delete all SDK diagnostics held by Google. Google handles those records under its applicable service terms and privacy policies.

Account deletion

Request deletion through Profile → Delete account or email neymanoff@gmail.com from the address used for Google sign-in in Curious Sheep.

After verifying account ownership, NNOff deletes your Curious Sheep sign-in account and associated data held by NNOff within 30 days and emails confirmation. This support-assisted process includes any cloud learning snapshot, account-access and download-limit records. Your Google account is unaffected. A later sign-in creates a new app account.

The account-deletion process also removes our active subscription, verification and purchase-binding records. A minimal hashed deleted-account guard can remain to prevent a delayed request or notification from restoring deleted data; it contains no saved words, recording, email or purchase token. Google-held payment records are handled by Google, and deleting the app account does not cancel renewal.

NNOff deletes correspondence about your deletion request within 30 days after completing it. Firebase's separate authentication-data retention is described above.

The request does not remotely erase files on your devices or device backups. To remove local words, progress, preferences and recordings, use Android Settings → Apps → Curious Sheep → Storage → Clear data on each device. This removes all app data on that device, including other local accounts and guest progress. Clearing local data alone does not delete your sign-in account. Manage device backups through your device and backup provider.

See Delete your Curious Sheep account for instructions without installing the app.

Service providers and international processing

Google provides sign-in, Firebase Authentication, ML Kit translation, Firebase Remote Config and Installations, Google Play and this Google Sites website. Google Cloud Run serves our hosted book catalog, authorized book downloads, subscription verification and optional account synchronization. Google Cloud Pub/Sub delivers Google Play status notifications to that server. Private book files, learning snapshots and subscription metadata use Google Cloud Storage and Firestore in europe-west1 (Belgium). We use an account identifier and download-limit records to check access and protect the service from repeated downloads. Google may process authentication information and technical service logs in other locations under its applicable terms. Email providers handle support messages you choose to send. These providers process information needed to operate their services; see Google's privacy policy. We may disclose information when required by applicable law.

Firebase Authentication processes data in the United States. Google and email providers may also process information in other countries. Google's published terms describe safeguards for applicable international transfers, including contractual protections and its Data Privacy Framework participation. See Firebase's international-transfer information. These are provider safeguards, not a claim that NNOff is certified under that framework.

Security and retention

Sign-in and hosted requests use encrypted HTTPS connections. Account synchronization requires a valid sign-in and server permission; the app does not give public access to the learning database. Android app-private storage and separate local account stores restrict ordinary access to saved learning data. This is encrypted transport and access control, not end-to-end encryption that prevents the service operator from processing the data. No storage or transmission method is completely secure.

Local learning data remains until you remove it or Android removes the app’s data. Cached recordings may be cleared sooner. The cloud keeps the current accepted learning snapshot until it is replaced by a later synchronization or removed as part of a verified account-deletion request. Signing out or removing a downloaded book does not delete that cloud snapshot. Private conflict-recovery copies on the device remain separate from the current cloud snapshot. Technical provider logs and backups follow the applicable provider retention rules. Account and deletion-request retention is described above; backup providers control their own copies. We keep other support correspondence only as long as needed to handle the issue and meet applicable legal obligations.

Your choices and rights

Depending on applicable law, you may request access, correction, deletion or a portable copy of personal information, object to processing, request restrictions, or withdraw consent where processing relies on it. Contact neymanoff@gmail.com. We may verify your identity and respond within the time required by applicable law. You may complain to your local data-protection authority. Local-only learning records are not uploaded to NNOff. If you choose account synchronization, NNOff processes your cloud learning snapshot to provide that feature; you can request access, correction, a portable copy or deletion through the privacy contact above.

Children

Curious Sheep is intended for adult language learners and is not directed to children. If you believe a child has supplied personal information to us, contact the privacy address so we can investigate and take appropriate action.

Changes

We will update this page and its date when our practices change. Material changes will be communicated as required by applicable law. New server, subscription or other data-processing features will require updated disclosures before introduction.

Questions and privacy requests

Contact neymanoff@gmail.com about your information.