Privacy Policy — Brown Noise · Sleep Sounds
App: Brown Noise - Sleep Sounds (com.serenity.brownNoise) Platforms: iOS and Android Last updated: 8 October 2026 Effective date: 8 October 2026
At a glance
Question
Answer
Do I need an account?
No. No sign-up, no login, no password.
Do you collect my name, email or phone number?
No.
Does anything leave my device?
Only anonymous purchase/subscription signals for the optional subscription. Your settings, mixes and sleep history never leave your device.
Do you listen to me or use my microphone?
No. All sounds are generated on your device.
Do you record my sleep?
Sleep sessions are estimated from playback time and stored only on your device. See §5.
Do you show ads or track me across other apps?
No ads, no advertising identifier, no cross-app tracking.
Do you collect my location?
No. The App never requests location permission.
Can I delete my data?
Yes. Delete it in the App, or delete the App to remove everything.
Do you sell my data?
No. We never have and never will.
Is this a medical device?
No. It is a relaxation and sleep-aid sound player.
1. Who we are
Brown Noise - Sleep Sounds ("the App", "we", "us", "our") is developed and published by an independent developer, who acts as the data controller for the purposes described in this policy.
Contact: eddietwchan@gmail.com
This policy explains what happens to your information when you use the App. It applies to the iOS and Android versions of Brown Noise.
2. Our approach in one paragraph
Brown Noise is a sound player. It contains no accounts, no social features and no advertising. The 38 built-in sounds and your custom mixes are synthesised and played entirely on your device, and everything you configure — volume, sleep timer, favourites, mixes, bedtime reminders and your sleep history — is stored locally in the App's private storage. We do not operate a server that receives your content. The only information that leaves your device is the anonymous purchase signal required to run the optional subscription, which is handled by our subscription provider Superwall and by the Apple App Store (or Google Play). We do not sell your data and we do not track you across other apps or websites.
3. Information we do not collect
We want to be specific, because "we collect nothing" is easy to say and hard to verify. The App does not:
require or offer accounts, sign-in, registration or passwords;
collect your name, email address, phone number, postal address, date of birth or payment details;
request access to your location, camera, microphone, photos, contacts, calendar, health, fitness, motion or biometric data;
read your device's advertising identifier (IDFA), or present an App Tracking Transparency prompt, because it does not track you;
run any third-party advertising SDK;
run any third-party analytics, attribution or crash-reporting SDK (there is no Firebase, Crashlytics, Sentry, Amplitude, Mixpanel, Meta/Facebook, AppsFlyer or Adjust in the App);
sell, rent or share your personal information with data brokers.
The only third-party SDK in the App with any telemetry surface is the subscription provider described in §8. There is no other code in the App that transmits information about you.
4. Information stored on your device
The App saves the following in its own private, sandboxed storage on your device. None of it is transmitted to us, and it is not accessible to other apps:
Preferences
Volume levels, sleep timer setting, audio quality, fade in/out, theme, haptics, app language
Library state
Favourite ("liked") sounds, recently played sounds, your custom mixes / collections
Sleep history
Up to 90 recent sessions: start and end time, duration, which sound or mix was playing, and how the session ended
Reminders
Your bedtime reminder, wind-down nudge and wake-alarm times
One-time flags
Whether you have already seen an onboarding hint or an in-app rating offer
You can erase this at any time:
In the App — clear your sleep history / reset your settings from the Settings screen.
By uninstalling the App — removing the App deletes all locally stored data.
Because this data never reaches us, we cannot see it, recover it or delete it on your behalf; it lives and dies with your device.
5. Sleep and listening data — please read
The App's Sleep tab shows a nightly report: hours listened, a goal tracker, an estimated stage split (awake / light / deep / REM), sleep cycles and averages.
These figures are an estimate derived from how long playback ran. They are not a measurement of your sleep.
The App has no sleep sensor and no access to your device's health or motion data. It cannot observe your physiology, your brain activity, your breathing or your actual sleep stages — no app that only plays audio can. The stage split is a mathematical model applied to listening duration (for example, treating a fixed cycle length), and the "wake time" is the moment a session stopped, which may simply be when you pressed pause.
Accordingly:
The App is not a medical device and is not intended to diagnose, treat, cure or prevent insomnia or any other condition.
Do not rely on this report for medical or health decisions. If you have a sleep disorder, please consult a qualified healthcare professional.
A "session" means audio was playing, not you were asleep.
Your sleep history is stored only on your device, as described in §4.
6. Audio
All noise is generated procedurally on your device (or played from sound files bundled inside the App). The App does not record audio, does not use the microphone, and does not need to be online to play sounds. Playback can continue in the background (for example, with the screen off) so that a session is not interrupted overnight; this is a local device feature and does not involve us.
7. Reminders, alarms and notifications
If you enable them, the App schedules local notifications for your bedtime reminder, a wind-down nudge and a wake alarm. These are scheduled by your device's operating system entirely on-device. We do not send you push notifications and we do not operate any server that knows when your alarm is set. You can turn these off at any time in the App's Settings, or revoke notification permission in your device's system settings.
8. Subscriptions and payments
The App is free to download and use. It offers optional auto-renewing subscriptions (for example, monthly and yearly, sometimes with a free trial) that unlock additional sounds, mixing and fade features.
Payment. All purchases are processed by the Apple App Store (or Google Play). We never receive or store your name, card number or billing address. We only learn whether a valid subscription is active, so we can unlock the right features.
Our subscription provider, Superwall. We use Superwall to display subscription offers, determine and restore entitlement, and measure how well different offers perform. To do this, Superwall receives:
your purchase and subscription status and the product you selected;
an anonymous, app-generated installation identifier (not your name, email or Apple ID);
basic device and app context (device model, operating system version, app version, country/region from the store);
which offer was shown, and whether a purchase, renewal, cancellation or restore occurred.
How it may be used. App functionality (to grant, renew, restore and revoke access) and analytics (to understand and improve conversion). It is not linked to your identity — there is no account and we never pass Superwall your name or email — and it is not used to track you across other companies' apps or websites.
Managing your subscription. You can view, change or cancel a subscription at any time in your App Store (or Google Play) account settings, and you can restore an existing purchase from within the App. Cancelling stops future renewals; the current period runs to its end.
This is the only information about you that leaves your device, and it exists solely to make the optional subscription work.
9. In-app rating prompt
The App can show the standard Apple or Google rating prompt and includes a "Rate the App" row that opens the store listing. These are provided by the operating system and the in_app_review plugin. The prompt is presented by the store, stores are limited in how often they may show it, and we do not receive your rating or review text through it. If you write a review, it is public on the store under your store account and is governed by the store's own policies.
10. Sharing content
If you use a share action (for example, to tell a friend about the App or share a mix), the share_plus plugin opens your device's standard share sheet. Nothing is transmitted until you pick a destination, and the content goes directly from your device to the app or service you chose. We do not see it, and we do not receive a record of what you shared.
11. Links to other websites
The App contains links that open in your browser: this Privacy Policy, the Terms of Use (Apple's standard end-user licence agreement), and the App's store listing. Once opened, those pages are governed by their own operators' privacy practices.
12. Third-party service providers
Provider
Purpose
What it receives
Privacy policy
Apple App Store / Google Play
Payment processing, subscription billing, distribution
Transaction and subscription data (handled by the store; not visible to us)
Apple: https://www.apple.com/legal/privacy · Google: https://policies.google.com/privacy
Superwall
Presenting subscription offers; entitlement and restore; conversion analytics
Subscription/purchase status, anonymous installation identifier, device/app context, offer-view and conversion events
These providers process the information above under their own privacy policies. We do not authorise them to use it for any purpose other than those listed.
13. How we use information
We use the limited information described above solely to:
play the sounds and mixes you select, and remember your preferences and favourites;
display your on-device sleep history and reminders;
present subscription offers, grant or restore access, and keep your entitlement accurate;
understand, in aggregate, whether our offers work, so we can improve the App;
comply with law and prevent fraud or abuse of the subscription system.
We do not use your information to train AI models, to build advertising profiles, or to contact you for marketing.
14. Legal bases (users in the EEA / UK)
Where the GDPR or UK GDPR applies, we rely on:
Performance of a contract (Art. 6(1)(b)) — processing the purchase signal to provide the subscription you asked for.
Legitimate interests (Art. 6(1)(f)) — keeping entitlements accurate, securing the App, preventing fraud, and measuring in aggregate whether our offers work. We have balanced these against your rights; because the data is anonymous, not linked to you and not used for tracking, the impact on you is minimal.
Consent (Art. 6(1)(a)) — where required, for example for notifications, which you may withdraw at any time in system settings.
You are not subject to automated decision-making that produces legal or similarly significant effects.
15. Your rights
Depending on where you live, you may have the right to access, correct, delete, restrict or object to the processing of your personal information, to data portability, and to withdraw consent. Because almost everything is stored locally on your own device, you can exercise most of these rights directly and immediately:
Access / portability — your settings and sleep history are on your device and visible in the App.
Deletion — clear your history in the App, or uninstall the App.
Objection / withdrawal — turn off notifications, or cancel your subscription in your store account.
For the small amount of subscription-related data held by our provider, or for any other request, email eddietwchan@gmail.com. We will respond within the timeframes required by law (generally within 30 days).
California residents (CCPA/CPRA): we do not sell or share personal information as those terms are defined by the CCPA, and we do not use it for cross-context behavioural advertising. You may request to know, delete or correct your information using the contact above. We do not discriminate against you for exercising your rights.
Hong Kong residents (PDPO): we handle personal data in accordance with the Personal Data (Privacy) Ordinance. As described above, we do not collect personal data from you through the App; any enquiry you send us by email is used only to answer you.
16. Children's privacy
The App is a general-audience sound player and is not directed to children. We do not knowingly collect personal information from children — and, as explained above, we do not collect personal information from any user of the App, because there are no accounts, no analytics and no server. If you are a parent or guardian and have a concern, you can remove all on-device data by uninstalling the App; if you believe a child has sent us personal information by email or through the store, contact us and we will delete it.
17. Data retention
On-device data (preferences, favourites, mixes, sleep history, reminder times) is kept until you delete it or uninstall the App. Sleep history is capped at the most recent 90 sessions and older entries are discarded automatically.
Subscription data is retained by Superwall and the app store for as long as needed to administer your subscription and to meet their legal, accounting and tax obligations.
Email you send us is kept only as long as needed to handle your enquiry, unless the law requires longer.
18. Security
Your settings and sleep history are stored in the App's private, sandboxed storage and are not readable by other apps. Where the App communicates with our subscription provider or the store, that communication is encrypted in transit (HTTPS/TLS), and payment data is handled by Apple or Google, not by us. No method of transmission or storage is completely secure, but we use commercially reasonable safeguards and we hold as little as possible in the first place.
19. International data transfers
The App itself does not send us your data. Subscription-related information handled by Superwall and the app stores may be processed in countries other than yours (including the United States), under those providers' contractual and security safeguards. Because the information is anonymous and not linked to your identity, it carries a low risk.
20. Changes to this policy
If we change how the App handles information, we will update this policy and revise the "Last updated" date above. Material changes — for example adding a new third-party service or a new category of data — will be highlighted in the App before they take effect, so you can review them and decide whether to continue. We will not apply a materially different use to information already collected without telling you first.
21. Contact
Brown Noise - Sleep Sounds — developed and published by an independent developer in Hong Kong.
Privacy questions, requests and complaints: eddietwchan@gmail.com
Appendix A — Apple "App Privacy" label (for reference)
This appendix maps the practices above to the App Store privacy questionnaire ("nutrition label") filed in App Store Connect. It is provided for transparency and to keep the policy and the store label consistent; it is not part of the binding policy.
Data used to track you: None.
Data linked to you: None.
Data not linked to you:
Purchases — purchase and subscription status, used for App Functionality and Analytics (via Superwall and the app store).
Data we do not collect: contact info, health & fitness, financial info (beyond the purchase signal above), location, sensitive info, contacts, user content, browsing history, search history, identifiers, usage data, diagnostics.
This document is provided for informational purposes and should be reviewed by qualified counsel before publication.