Privacy Policy · SentenceDeck
Effective Date
August 22, 2026
Scope
This policy applies to the iOS app SentenceDeck (the “App”) and the services used to provide its optional premium text-to-speech feature.
Quick Summary
- No SentenceDeck account or sign-up is required.
- System voice, microphone recordings, practice progress, articles, and generated audio are handled on your device.
- Premium voice sends the text you choose and the required voice settings through a Cloudflare Worker to Google Cloud Text-to-Speech.
- Apple processes In-App Purchases. SentenceDeck uses limited transaction and character-wallet records to validate purchases and prevent duplicate charging.
- We do not use advertising SDKs, sell personal data, or track you across apps and websites.
Data We Process
1) Content you choose for premium voice
When you request premium audio, the App processes:
- The sentence text you submit for speech generation.
- Language, voice, speaking style, and generation settings required to create the audio.
- Request identifiers needed to authorize the request, reserve characters, and prevent a completed request from being charged twice.
The App sends this information to a Cloudflare Worker operated for SentenceDeck. The Worker forwards the speech request to Google Cloud Text-to-Speech, including Gemini-based TTS models where selected. The generated audio is returned to the App and saved locally.
System voice uses Apple’s on-device speech engine and does not send sentence text to the SentenceDeck premium-voice service.
2) Purchases, wallet records, and service diagnostics
Apple processes payments. SentenceDeck receives transaction information needed to validate a purchase and credit the correct character pack. We do not receive your full card or bank details.
To secure premium requests and keep the character balance accurate, the service processes limited records such as:
- App transaction and request/session identifiers.
- Character reservation, commit, release, and wallet-balance records.
- Product identifier, transaction status, and credited character amount.
- Technical diagnostics such as endpoint, voice/model selection, status, timestamps, and error context.
Infrastructure providers may process standard network information, such as an IP address and user agent, as part of security and operational logging.
3) Microphone and practice data
If you grant microphone access, SentenceDeck records your voice so you can compare it with the reference sentence. The recording and practice state are processed locally. SentenceDeck does not send your microphone recording to its premium-voice service and does not use it for AI pronunciation scoring.
4) Local articles and audio
Your imported or pasted articles, practice progress, reference audio, and microphone recordings are stored in the App’s local container as needed for the feature. SentenceDeck does not provide developer-operated account sync for this library.
How Premium Voice Data Flows
- App → Cloudflare Worker for request authorization and billing control.
- Cloudflare Worker → Google Cloud Text-to-Speech for speech generation.
- Generated audio → App, where it is cached on your device.
Authentication and character-wallet records may be stored in service infrastructure, including Google Cloud Firestore, to validate purchases and maintain the wallet across supported devices associated with your Apple transaction identity.
Device Backup, Export, and Import
Premium audio is eligible for iCloud or computer device backup when that backup is enabled and has sufficient space. Free system-voice audio can be regenerated and may be excluded from device backup.
Device backup is controlled by Apple and the device owner. Premium audio returns only as part of a compatible full-device restore. Deleting and reinstalling SentenceDeck alone does not restore that audio.
When you manually export audio:
- SentenceDeck creates a temporary ZIP or merged audio file and presents Apple’s system share or document controls.
- You choose the destination, such as Files, iCloud Drive, AirDrop, email, or another compatible service.
- SentenceDeck does not receive access to the destination account and does not upload the file to a developer-operated storage service.
- Temporary export files are removed from the App’s scratch space when the export flow ends.
When you import a SentenceDeck ZIP, the package is copied to temporary App storage, checked for compatible content and audio, and processed locally. The temporary copy is removed when the import session ends. Compatible articles and audio can be restored; practice progress is not included. Audio generated with incompatible voice or style settings may be skipped rather than attached to the wrong configuration.
Data Retention
- Local content and audio: Remain on your device until you remove them, clear generated audio, or delete the App. Copies you export remain wherever you chose to save or share them.
- Premium sentence text: Processed to complete speech generation. We do not intentionally store full submitted text in our long-term wallet database.
- Short-lived authentication/session records: Retained only for their configured security lifetime.
- Purchase, wallet, fraud-prevention, and diagnostic records: Retained as needed to operate the service, reconcile purchases, prevent abuse, resolve disputes, and meet legal or accounting requirements, then minimized or deleted when no longer needed.
Your Choices
- Use free System voice if you prefer on-device speech generation.
- Decline microphone access; reference-audio playback remains available without recording your voice.
- Clear generated audio or remove articles from inside the App.
- Use Settings → Backup & Export to create or import a user-controlled copy of compatible audio.
- Stop using premium voice to prevent future text from being sent for cloud generation.
- Contact us to request deletion of eligible server-side records linked to your App transaction identifiers.
Service Providers
We do not sell or rent personal data. We share limited data only with providers needed to operate the selected feature:
Terms and EULA
Use of the App is also governed by Apple’s standard End User License Agreement:
Changes to This Policy
We may update this policy when the App or its supporting services change. We will update the Effective Date when revised terms are published.
Contact
For privacy questions or eligible deletion requests:
- Email: contact@kuroneko-cmd.dev