Privacy Policy · SentenceDeck

Effective Date

February 23, 2026

Scope

This policy applies to the iOS app SentenceDeck (the “App”) and its Cloud TTS infrastructure.

Quick Summary

• No sign-up account is required to use the App.
• The App has two speech modes:
  • System TTS: on-device, offline.
  • Cloud TTS: sends request data through our Cloudflare Worker to Google Cloud Text-to-Speech.
• Generated audio files are stored locally on your device.
• We do not run advertising SDKs and we do not sell personal data.

Data We Process

1) Data used for Cloud TTS conversion

When you use Cloud TTS, we process:

• Text you submit for conversion.
• Voice/language/model options needed to generate speech.
• Required request identifiers (for example, app transaction binding headers) to validate usage and credits.

2) Security and billing metadata

To secure the service and account for Credits, we process limited metadata such as:

• Authentication challenge/session identifiers.
• Credit reservation/commit/release records and character counts used for billing accuracy.
• Service diagnostics data (for example, endpoint, model/voice, status, and error context).

Cloud providers may also process network metadata (for example, IP address and user-agent) as part of standard infrastructure logging.

3) In-app purchases

Payments are processed by Apple. We receive transaction metadata needed to validate purchases and update Credits.

We do not receive full card or bank payment details.

How Data Flows

For Cloud TTS:

1. App -> Cloudflare Worker (request gateway)
2. Cloudflare Worker -> Google Cloud Text-to-Speech (speech generation)
3. Audio response -> App, then saved locally on device

For Credits/auth:

• App/Worker -> auth and billing services (including Google Cloud Firestore records for credit ledger and wallet state)

Local Audio Storage

Generated audio files are stored locally on your device cache. You can clear them in the App settings.

Data Retention

• Local audio files: remain on your device until you clear cache or remove the App.
• Cloud TTS text content: processed for request completion; we do not intentionally persist full text in our own long-term databases.
• Auth challenge/session records: short-lived KV records with TTL (for example, challenge about 2 minutes; refresh session up to 30 days, configurable).
• Billing/security records: retained as needed for fraud prevention, dispute handling, and accounting, then minimized or deleted according to operational needs.

Your Choices

• Use System TTS if you prefer offline processing.
• Clear generated audio from Settings -> Storage -> Clear Cache.
• Stop using Cloud TTS at any time to withdraw from cloud processing for future requests.
• Request deletion of server-side records linked to your app transaction identifiers by contacting us.

Data Sharing

We do not sell or rent personal data.

We share limited data only with service providers needed to run the feature:

• Cloudflare Privacy Policy
• Google Privacy Policy
• Apple Privacy Policy

Terms and EULA

Use of the App is also governed by Apple’s standard End User License Agreement (EULA):

• https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Changes to This Policy

We may update this policy from time to time. We will update the Effective Date when changes are published.

Contact

For privacy questions or deletion requests:

• Email: contact@kuroneko-cmd.dev