NDTD Language Shadower operates primarily on your device. Your media files, recordings, bookmarks, and notes are stored locally and are never sent to our servers.
Auto Generate: When you use this feature, the app sends the topic you select (e.g., "job interview"), an App Attest assertion, and device security signals to our backend to generate audio.
We do not collect your name, email, contacts, photos, or precise location, and we do not use third‑party analytics or advertising.
For security and purchase verification, we may process: App Attest key ID, App Attest risk metric, purchase transaction claim IDs, and IP address for rate limiting.
We use App Attest signals to prevent abuse and enforce free‑use limits for Auto Generate.
We use purchase transaction claim IDs to verify paid generations.
We use IP address for rate limiting and service protection.
Imported files, voice recordings, bookmarks, scan results, and study notes remain on your device for your personal language learning practice.
All data—imported media, voice recordings, bookmarks, notes, and scan-generated audio—is stored locally using iOS storage (UserDefaults, Documents directory, Keychain).
Google Drive and OneDrive: If you connect these accounts, OAuth tokens are stored securely in your device Keychain. We do not receive or store these tokens on our servers.
Backend storage (limited): App Attest key ID, risk metric, and purchase transaction claim IDs are stored to prevent fraud and verify purchases.
Data retention: We retain security and transaction records only as long as needed for fraud prevention, accounting, and legal requirements. You may request deletion by contacting us.
You
└─ App (on device)
├─ Local files/recordings/notes (stay on device)
├─ OAuth to Google/Microsoft (direct, tokens stored in Keychain)
└─ Auto Generate request
├─ Topic ID + App Attest assertion → Backend
├─ Backend → OpenAI (script + TTS)
└─ Backend → App (audio + optional subtitles)
Backend stores (limited):
- App Attest key ID + risk metric
- Purchase transaction claim ID
- Rate-limit counters (may include IP)
• Microphone: Used only to record your voice practice sessions. Recordings are stored locally.
• File Access: Used to import media and subtitle files from your device or cloud providers for local playback.
• Camera: Used only when you use Scan to capture book pages. Images are processed on your device (OCR and text-to-speech); they are not sent to our servers.
This app does not use third-party analytics, advertising, or tracking.
URLs & Cloud: The app connects to user-provided URLs (Google Drive, OneDrive, Dropbox, or direct links) when you stream or download. For Google Drive and OneDrive sign-in, the app uses OAuth and connects directly to Google/Microsoft—we do not receive your credentials or file content.
Auto Generate: Uses our backend service to produce audio from the topic you select. We may process limited security signals (App Attest) and purchase transaction IDs.
We use OpenAI as a processor to generate scripts and text-to-speech audio based on your selected topic.
Our app does not knowingly collect any information from children. Since we do not collect any personal information, this policy applies to all users regardless of age.
We may update this Privacy Policy from time to time. We will notify you of any changes by posting the new Privacy Policy in the app and updating the "Last Updated" date.
If you have any questions about this Privacy Policy, please contact us at: