Privacy Policy
Applies to the Thủ thỉ app on the web, Android and iOS. Last updated October 16, 2026. This is the English version of the Vietnamese policy.
Thủ thỉ helps parents tell bedtime stories to their children. The app is for adults: parents or relatives sign in and use it. Children only listen to stories and never create accounts.
This page explains what the app collects, what it is used for, who it is shared with and how to delete it.
1. Data the app collects
| Data | Used for | Stored |
|---|---|---|
| Email, display name, Google or Apple account ID (when you sign in with Google or Apple) | Signing in and connecting devices in the same family | Thủ thỉ server |
| Family profile: your child's name or nickname, date of birth or age, interests, bedtime, and the names and roles of people in the family | Writing age-appropriate stories, using your child's name, reminding you at story time | On the device and in the family account |
| Stories you create and save | Viewing them again on every device in the family | On the device and in the family account |
| Recordings of parents reading stories | Letting your child hear a parent's voice again | File storage on the server. If "Keep voice recordings on this device only" is on, they are stored only on the device |
| Voice samples for creating an AI voice (only when a parent chooses to create one) | Creating a voice that sounds like the parent | Sent to an AI voice provider (ElevenLabs or Google Gemini, see section 2), together with a consent recording read by the same person if the provider requires it. Can be deleted in Settings |
| Feedback and story reports | Fixing problems, improving stories, handling inappropriate content | Thủ thỉ server |
| Anonymous usage statistics (for example: a story was created, a story was finished) | Learning which features are useful. Does not include names, email or story text | Thủ thỉ server, kept for up to 90 days. Can be turned off in Settings |
| Notification subscription (if story-time reminders are on) | Sending a reminder before bedtime | Thủ thỉ server |
| Star balance and Star usage history | Counting use of AI features | Thủ thỉ server |
| In-app Star purchases: transaction ID, pack purchased and time of purchase (no card or payment details) | Crediting Stars exactly once per transaction and checking it with Apple or Google when needed | Thủ thỉ server. Payment is handled by Apple or Google; Thủ thỉ never receives card numbers |
The app shows no ads. The app does not sell data. The app does not use data to track you across other apps or websites.
2. Data sent to AI services
Some features use outside AI services. The app asks for your permission before the first use. You can turn this on or off in Settings → Privacy → "Use AI to write and read stories".
- Writing stories: the topic, characters, age, length and any idea you enter are sent to one of the language-model providers: Google Gemini, Anthropic Claude or OpenRouter. Your child's name is replaced with a placeholder before sending and filled back in when the story returns to the app.
- AI cover art: when a parent chooses to draw art, a short description of a scene from the story is sent to the image provider (currently Google Gemini) to paint the cover. The description does not include your child's name. The finished picture is stored in the family account and is deleted when you delete the account (the last person in the family).
- AI voice reading: the story text is sent to a voice provider (ElevenLabs or Google Gemini, depending on the voice you choose) to be read aloud. The audio is saved so that replaying it doesn't require sending the text again.
- Creating a voice like a parent's: a voice sample of about 30 seconds is sent to an AI voice provider (ElevenLabs or Google Gemini) to create the voice. Before sending, the app asks you to confirm that the voice is your own and that you agree to send the recording. If the provider needs to verify the owner, you also read a consent sentence; that recording is sent too, and the app does not keep it after the voice is created. The provider keeps the voice until you delete it. You can delete this voice in Settings; the app deletes it at the provider too.
Thủ thỉ may switch between these providers or upgrade a model without changing the kind of data sent. When a new provider is added, the list in this section is updated before it is used. These services handle data under their own policies. Thủ thỉ sends only the data needed for each task. Without AI, the app still tells stories from its built-in library and sends nothing to AI services.
3. Where data is stored
The server and file storage run on Cloudflare. The website is served through Cloudflare and GitHub Pages. Data is transmitted over an encrypted connection (HTTPS).
4. Who can see the data
- Stories and voice recordings can be seen and heard only by people in the same family.
- The people who run Thủ thỉ read story content only when you send feedback or report that story, to handle the report.
5. Children
Accounts are created and managed by adults. The app keeps only the information about the child that parents enter themselves (nickname, age, interests). This information is used only to write and tell stories for the child. Parents can edit or delete it at any time.
6. Your rights
- View and edit the family profile in the app.
- Turn off usage statistics, turn off AI use, or choose to keep voice recordings on the device only.
- Delete an AI voice, delete individual stories, or delete the whole account. See how to delete your account on this page.
7. Retention
- Accounts, stories and voice recordings are kept until you delete them.
- When you delete your account: your account, sessions and reports are deleted immediately. If you are the last person in the family, the family profile, stories and voice recordings are deleted too.
- Feedback you sent is kept but unlinked from your account.
- Anonymous statistics are deleted automatically after 90 days.
8. Changes to this policy
When the policy changes, the update date at the top of the page changes too. Major changes will be announced in the app.
9. Contact
Email: nguyen.minh.mz98@gmail.com. You can also send questions through the feedback prompt that appears after each story in the app.