Privacy policy

Last updated: 8 October 2026

This policy explains how Baku uses information to provide bedtime stories for parents and caregivers.

Who operates Baku

Baku is developed and operated by Dekan Studio — an independent developer. In this policy, “we”, “us” and “our” mean Dekan Studio, which is responsible for the personal information processed to provide Baku. Contact us at [email protected].

Information used by the app

Account and sign-in information: account identifiers, profile information and information associated with the sign-in method you choose.
Child profiles and story preferences: details supplied by a parent or caregiver, including a child’s name, birth year, month and year, or full birth date according to the detail you choose, age derived from those details, gender, interests and story language, to personalize stories. A child profile is not a separate account.
Stories and media: personal story requests, generated text, narration, images and related processing records.
AI sharing decisions: your agreement or withdrawal, the disclosure version and language, its wording, and the time recorded by Baku. These records document your choices without adding child details.
App activity: playback progress, favorites, feedback, notification settings and usage allowances.
Usage analytics: screen-view events and SDK-collected usage and technical information, such as app-instance identifiers, session activity, app version, device and operating-system details, to understand how the app is used and improve it.
App installation and notifications: an installation identifier, device platform, timezone, app language, push notification token when push notifications are enabled and permitted, notification preferences, and bedtime reminder time and days. These help deliver notifications and manage reminders.
Purchases: store purchase information used to verify subscriptions and other entitlements and prevent purchase reuse.
Diagnostics and security: crash reports, app and device information, IP addresses, authentication and security records used to maintain the service and investigate failures.
Support correspondence: your email address, messages and the information needed to investigate your request or verify account ownership.

Using Baku as a guest still involves processing information. Guest mode creates an account identifier and session credentials, and stores preferences and playback progress so you can browse and listen without registering. Guest accounts do not have child profiles. App installation and notification information may also be processed before registration.

Why this information is used

Baku uses this information to manage accounts, personalize and deliver stories, remember listening activity, understand app usage and improve the experience, deliver enabled notifications and manage reminders, verify purchases, respond to support requests and protect the service.

Where applicable law requires a legal basis, we process information as needed to provide the service you request, for legitimate interests such as service security and reliability, to meet legal obligations, or with your consent where required. You may withdraw consent by contacting us; this does not affect processing that was lawful before withdrawal.

Services that help provide Baku

We use service providers that protect personal information to a standard at least equivalent to the protections described in this Privacy Policy and required by applicable app-store rules. Information is shared as needed for the features described below:

Cloudflare: website and media delivery, stored media and account-deletion recovery records.
Google and Apple: sign-in information when you choose their sign-in services, and purchases processed through their stores.
Qonversion: account and purchase identifiers, subscription status and entitlement information used to verify purchases.
OpenAI — story text and checks: your child’s name, age in months derived by Baku, gender and interests; story language and locale; selected themes, lessons, routine and length. These details help create, revise and check stories. Revisions also send the original story and requested change. Baku stores the birth-date detail you supply, but sends the derived age in its personalization fields rather than that recorded birth date.
OpenAI — cover images: a scene description derived from the generated or revised story. Baku instructs the text-generation service to describe generic fictional characters and omit identifying profile details, then removes the supplied child’s name from the cover description. This reduces identifying details; it does not guarantee that the description is anonymous.
Microsoft Azure or ElevenLabs — narration: the story text and speech-synthesis settings, such as the voice, model, language and speaking speed, as applicable to the service producing the requested narration. The text may contain your child’s name or other personal information already included in the story. Baku does not send a separate child-profile record for narration.
Brevo: recipient addresses and message information for authentication and account-deletion confirmation emails when that email service is used.
Google Firebase Crashlytics: diagnostic information used to identify crashes and improve reliability.
Google Analytics for Firebase: screen-view events and SDK-collected usage and technical information used to understand app usage and improve the experience.
Google Firebase Cloud Messaging and Apple Push Notification service: push tokens and notification content and routing data used to deliver enabled story notifications to your device. On iOS, push delivery also uses Apple’s push notification service.

Story push notifications are sent through these delivery services. Bedtime reminders are scheduled locally on your device; their enabled status, time and days are also stored by Baku with your app installation settings.

Crashlytics collection is enabled by default. Reports include exception types and stacks, screen breadcrumbs and session phase, as well as SDK-collected information such as app version, device and operating-system details, installation identifiers and crash timing. Baku’s own diagnostic reports do not deliberately include child details, story text or raw story identifiers.

Firebase Analytics collection is enabled by default, including in guest mode. Baku sends screen names using route patterns rather than individual story identifiers or URL query parameters. These screen-view events do not include child details or story text. The Firebase SDK also collects usage and technical information automatically. See the analytics retention explanation below.

Providers may process information outside your country. Their applicable service terms, data-processing agreements and account settings govern processing and retention, subject to the protections described in this policy and applicable law. Where required by law, international transfers must use an applicable transfer mechanism or safeguard. Contact us for information about processing relevant to your account.

We may also disclose information where required by law, to respond to a valid legal request, or as necessary to protect users and the service against fraud, abuse or security threats.

Before your first new personal AI request, Baku asks for your explicit permission to share the information described above with OpenAI, Microsoft Azure and ElevenLabs for story text, checks, cover images and narration. This permission applies to all child profiles in your registered account and is recorded against a disclosure version. It is separate from accepting the Terms of Use. A materially changed disclosure requires agreement to its new version before making new AI requests.

You may decline and continue browsing, reading or listening to available content and managing child profiles. Declining does not grant permission to generate or revise personal content. Only provide child information you are authorized to share.

Manage or withdraw permission at Settings → AI data sharing. Withdrawal blocks new AI requests. Requests already accepted by Baku, including their subsequent processing steps and retries, may finish using the permission recorded when they were accepted. Withdrawal does not delete information already sent or content already created. For removal, use the account-deletion process or contact support about a privacy request.

AI processing and model training

Baku does not submit this personal information for model training. Personal AI generation is released only after verifying that the provider configurations and applicable terms support this policy: no voluntary OpenAI API data sharing for training, ElevenLabs model-improvement data use disabled, and the applicable protections for Azure’s real-time text-to-speech service.

Not using data for training does not mean that providers retain no data. Processing records, safety and abuse-monitoring records, and any saved service history remain subject to the retention and deletion controls described in this policy. Requesting that an OpenAI response not be saved for later retrieval is a separate control from training choices. See OpenAI’s data controls, ElevenLabs’ model-training choices and Microsoft’s text-to-speech data handling.

Children and caregivers

Baku accounts are intended for adults who have reached the age of majority where they live. Children may enjoy stories under a parent’s or caregiver’s supervision. Child profiles are managed by adults and are not separate child accounts. Provide child information only if you are authorized to do so, and avoid including sensitive details that are unnecessary for a story.

If you believe a child has provided information without appropriate adult authorization, contact us so we can investigate and arrange its removal where appropriate.

Account deletion

You can use the in-app deletion option or follow the external request instructions. Support must verify account ownership before submitting an external request. Once accepted, deletion disables account access and starts irreversible erasure; acceptance does not mean processing has finished.

With a current guest session, open Settings → Account information → Permanently delete account; registration and email verification are not required. Guest activity, sessions and account-linked installation records are erased through the same process and retention exceptions. Guests receive no completion email. Device-wide language, playback speed and bedtime settings remain and may be sent again for a new account. A new guest identity does not restore the old account's history.

The external email process is for registered accounts whose ownership can be verified. If a guest session is lost, an account ID or sender email alone does not prove ownership; Baku currently has no established external guest verification or recovery process. Uninstalling or reinstalling does not recover the lost guest. See the guest deletion limitations; do not send passwords, tokens or child information.

When you delete your Baku account, we erase the associated personal information from Baku’s active systems, subject to the limited retention described below. Information previously processed by service providers is subject to the retention periods and deletion mechanisms applicable to those services. Completion of Baku’s account-deletion process does not confirm that every provider-held copy has been deleted.

Erasure covers child profiles, private stories and their revisions, personal audio and images, listening activity, favorites, personal feedback, notifications, account-linked app installation records (including push tokens, notification preferences and reminder settings), account identities, sessions, AI sharing decisions and related processing records. Shared stories and genuinely aggregate statistics remain. Minimal purchase fingerprints are kept to prevent reuse, without the original transaction value or an account link.

Data held by service providers after account deletion

Baku automatically erases the account data and personal media it manages. When your account-deletion request is accepted, Baku will automatically send deletion requests to Qonversion, OpenAI, ElevenLabs and Brevo for your associated personal data processed by those services. Sending a request does not mean the provider has completed deletion; processing and any retained records remain subject to the applicable retention and deletion rules described below.

Google Analytics for Firebase and Firebase Crashlytics: Baku currently has no automatic process that deletes Analytics or Crashlytics records when you delete your Baku account. These services use their own app-installation identifiers; Baku does not set your Baku account ID as their user ID. Deleting the account or its app installation records in Baku does not itself delete records already sent to Firebase. See the separate Analytics and Crashlytics retention explanations below. Contact support about a privacy request involving these records; identifying the relevant provider-held records may require additional information.
Cloudflare R2: personal media: Baku sends deletion requests for the private story audio, images and related stored copies it manages, including its trash copies. Limited records used to reapply account deletion after a backup restore are retained as described below. This does not describe deletion of Cloudflare’s separate website or security records.
Qonversion: purchases and entitlements: Baku removes its own account-linked purchase and subscription records, apart from the minimal purchase fingerprints described below. Baku will automatically request deletion of your associated customer data held by Qonversion through its customer-data deletion process. Removing a Qonversion customer does not cancel a store subscription. See Qonversion’s customer deletion documentation.
OpenAI: story generation: Baku deletes its own copies of personal prompts, generated content and related processing records. For new text-generation requests through OpenAI’s Responses service, Baku asks OpenAI not to save the response for later retrieval. This does not erase older saved responses or exclude all provider security and abuse-monitoring records. Baku will automatically request deletion of saved responses associated with your account through OpenAI’s individual response-deletion mechanism. Image processing and other retained records follow the applicable OpenAI data controls.
Microsoft Azure: narration: Baku deletes the personal narration and synthesis records it stores. Microsoft states that its real-time text-to-speech service does not retain the input text or generated audio, so there is no saved synthesis content from that mode to delete at Azure. This statement does not cover batch synthesis, custom-voice training or separately stored diagnostics, which have their own controls. See Microsoft’s text-to-speech data handling.
ElevenLabs: narration: Baku deletes its own copies of personal narration and synthesis records. Baku will automatically request deletion of narration history associated with your account that is retained by ElevenLabs, using its individual history-item deletion mechanism. See ElevenLabs’ history deletion documentation.
Brevo: email delivery: Baku removes earlier account-linked authentication email records as part of erasure. If an account email address is available, Baku temporarily retains it to arrange a deletion-confirmation email after active-system erasure completes. Related delivery records may remain for delivery and troubleshooting. Brevo may hold recipient information, delivery logs and stored email previews, including for that confirmation. Baku will automatically request deletion of your associated recipient information, email logs and stored previews through Brevo’s controls for contacts and transactional logs and previews. A deletion-confirmation email may create new delivery records, which remain subject to the applicable retention and deletion rules.

Completion of erasure in Baku, including a confirmation email, refers to Baku-managed active account data and personal content, subject to the retention exceptions below. It does not certify that all provider records have been erased. For a privacy request about data processed for Baku by these services, contact [email protected]. The provider references explain available controls; they do not replace Baku’s responsibilities under applicable law.

How long information is kept

We complete erasure of personal account data from Baku’s active systems within 30 days after your deletion request is accepted, subject to the retained information described below. Account access is disabled and erasure starts on acceptance. For email requests, account ownership must be verified before acceptance; sending an email alone does not mean that your request has been accepted or erasure has finished.

Account information, AI sharing decisions and personal content: Kept to provide your account, document your permissions and provide requested features, then erased through the account-deletion process, subject to the limited retention purposes described here.
Protected backups: Each backup copy is retained for no more than 90 days from its creation. Backups are isolated from ordinary use, and deletion is reapplied before any restored data is used.
Deletion records: We keep a record that your account was deleted for up to 120 days after deletion is complete. This helps us prevent your data from being accidentally restored. Your account cannot be recovered. If deletion is still in progress, we keep the request until it is complete.
Firebase Analytics: Screen-view events, app-instance identifiers and SDK-collected usage information help us understand and improve Baku. Our policy limits user-level and event-level data retention to 2 months, without resetting user-data retention on new activity. Google deletes expired data in its monthly deletion process, so this does not mean every record disappears exactly two months after collection. Standard aggregated reports are not covered by this setting and may remain longer. Deleting a Baku account does not automatically delete Analytics records. Contact support about a privacy request involving these records. See Google’s retention explanation.
Firebase Crashlytics: Crash reports and associated installation identifiers help diagnose failures and improve reliability. Firebase states that it keeps crash stack traces, extracted minidump data and associated identifiers for 90 days before starting to remove them from live and backup systems. This is not a guarantee that every copy is gone on day 90. Baku account deletion does not automatically delete these reports. See Firebase’s privacy and retention information.
Support correspondence: We keep support email addresses, messages, attachments and verification correspondence while handling your request and for no more than 90 days after it closes, to resolve follow-up questions or disputes. If you request deletion of this information, we remove it from active support mailboxes within 30 days after accepting your verified request, unless the minimum information is still needed for an open request or a legal obligation. We retain that minimum only until the request is resolved or the obligation ends. Baku account erasure does not itself erase support mailboxes; support handles their removal separately. Any retained backup copies follow the applicable backup lifecycle.
Email delivery at Brevo: Brevo processes recipient information and delivery records to send authentication and account-deletion confirmation emails, troubleshoot delivery and protect against spam. Our policy requires transactional logs for all Baku senders to expire after 1 month; deletion can take up to another 24 hours. Email preview storage must be disabled for new emails. Disabling previews does not remove older previews, which are handled separately through the applicable deletion controls. These settings also cover new records created by the deletion-confirmation email after account erasure. Contact records are separate from transactional logs and previews and are handled through the provider deletion process. See Brevo’s retention controls.
Deletion-confirmation recipient in Baku: An available verified email address is kept while account erasure is in progress and then while its confirmation email is queued or being retried. Baku removes the recipient from the delivery job when sending succeeds, permanently fails or is cancelled. Delivery failure does not undo account erasure. This removal does not erase copies in protected backups, the recipient’s mailbox or Brevo’s separate delivery records.
Other diagnostics and security records: We retain only the records needed for an unresolved technical incident, an active abuse or security investigation, or a specific legal obligation. We review them when the incident or investigation closes or the obligation ends, and delete them when none of those reasons remains. Security counters and revoked-token markers expire according to their security purpose; their expiry does not delete separate server logs or backups. Provider-held records follow the relevant service’s retention and deletion arrangements.
Purchase fingerprints: Minimal pseudonymous fingerprints, without an account link or the original transaction value, remain for as long as needed to prevent reuse of purchases belonging to a deleted account, including lifetime purchases. They are not fully anonymous.

Erasure from Baku’s active systems does not mean all protected backups or service-provider records have disappeared at the same time. Store payment and accounting records are controlled by Google Play or Apple under their own policies.

Your choices and rights

You can review and withdraw your AI sharing permission in Settings → AI data sharing, as explained in the AI permission section. Withdrawal is separate from deleting a child profile, a story or your account.

You can delete a child profile in Baku. Deleting a child profile does not automatically delete stories or narration already created using that profile, or personal information already included in those stories and recordings. Deleting your Baku account is a separate process that also erases private stories and personal media, subject to the retention exceptions described above. See the account deletion instructions, or contact support to request removal of specific personal information.

Depending on applicable law, you may request access to, correction of, deletion of or a portable copy of your personal information, object to certain processing, or request that processing be restricted. Contact [email protected] to make a request. We may need to verify your identity, and exceptions may apply under law. You may also have the right to complain to your local data-protection authority.

Baku currently has no in-app switch to turn off Firebase Analytics or Crashlytics collection. Contact support about privacy requests concerning these services. Notification settings control notifications and reminders; they do not turn off analytics or crash reporting.

You can manage story push notifications and bedtime reminders in Baku, control notification permissions through your device settings, and request account deletion without reinstalling Baku. Deletion does not cancel store subscriptions or delete your Google or Apple account. Downloaded copies may remain on your devices after account deletion. Reconnecting the app does not guarantee their removal.

Website visits

The Dekan Studio website uses Cloudflare Web Analytics to measure visits and page performance and help us improve the site. Cloudflare processes page-view and performance measurements through a script on website pages. This website analytics service is separate from Firebase Analytics in the Baku app. Read more about Cloudflare Web Analytics and Cloudflare’s privacy practices.

Cloudflare also processes connection information, such as IP addresses and requested pages, to deliver and protect the website. The website does not submit account-deletion requests itself. Email links open your email application.

How we protect information

We use HTTPS/TLS to protect information transmitted between your device and our services. Administrative access is restricted to authorized personnel, and our databases are not directly exposed to the public internet.

Protected backups are isolated from ordinary use. When a backup is restored, account deletions are reapplied before the restored data is used. See “How long information is kept” for backup retention periods.

No storage or transmission method is completely secure. Do not send passwords, sign-in codes, access tokens or unnecessary child information to support.

Changes to this policy

We may update this policy as Baku or its data practices change. The date above identifies the latest revision. Material changes will be communicated through the service or other appropriate means where required by law. See also our Terms of Use.