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Privacy Policy

Effective date: April 1, 2026 · Last updated: August 3, 2026

Slo ("we," "us," or "our") operates the Slo application for iOS, Android and Mac (the "App") and the slonoise.com website (the "Website"). This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our App or Website. Please read this policy carefully. By using the App or Website, you agree to the collection and use of information in accordance with this policy.

The App has no user accounts. You never register, sign in, or give us a name. Instead, each installation is assigned a small set of randomly generated identifiers when the App first runs. These identifiers do not tell us who you are, but they are pseudonymous rather than anonymous: they let us and our providers link your activity across sessions until you uninstall the App. Section 4.1 explains how to ask us to delete the data held against them.

1. Information We Collect

1.1 Information You Provide

  • Feedback and support messages. If you use the in-app feedback form, you provide a message and may provide an email address. The App attaches technical context to that message before sending it: your installation identifier, the date you first opened the App, whether crash reporting is enabled, your device manufacturer, model, type and operating system version, your system and app language, the App version and build, whether you have an active subscription, the number of days since you installed the App, your number of active days and total plays, your most-played sounds, and the names of your favourites and saved mixes. If you would rather not send that context, email us directly instead of using the form.
  • Support and feature requests submitted elsewhere. Our App Store support link opens a form hosted by Tally, and the "Feature requests" link in the App's settings opens a portal hosted by Featurebase. Anything you type into those forms is collected by those providers under their own privacy policies, in addition to reaching us.

1.2 Information Collected Automatically

When you use the App, we and our third-party service providers may automatically collect:

  • Device information: device model, manufacturer, brand, operating system version, whether the device is physical or emulated, device language, and time zone. On iOS this includes the Identifier for Vendor (IDFV).
  • App usage data: sounds played, playback duration, timer and fade-out settings, mix configurations, favourites, feature interactions, paywall views, and navigation events.
  • Advertising identifiers: the IDFA on iOS or the Google Advertising ID on Android, used for advertising only where you have given the applicable consent. On recent Android versions our advertising provider may also use Google's Privacy Sandbox interfaces, including the Topics API, to select ads.
  • Approximate location: our analytics and advertising providers derive an approximate location, typically at city or region level, from your IP address. The App does not request or use precise device location, and it holds no location permission.
  • Crash, performance and diagnostic data: error logs, stack traces, and device state at the time of a crash. On Android we also collect the operating system's record of why the App last stopped, including the termination reason, process importance, and memory in use at the time. We use this to diagnose playback being cut short overnight.
  • Installation identifiers: a randomly generated UUID used across our analytics and crash reporting, a separate generated identifier used for subscription management, and the app-instance identifier assigned by Google Analytics for Firebase. These are not linked to your name or email unless you send us one through the feedback form.

1.3 Purchases and Subscriptions

If you buy a subscription or a one-time unlock, our subscription provider (RevenueCat) receives and stores your purchase history: which products you bought, purchase and renewal dates, trial and billing status, transaction amounts, and store receipts validated with Apple or Google. We do not receive or store payment card details; those stay with Apple and Google.

We also attach descriptive attributes to your subscription profile so we can understand who upgrades and support you if something goes wrong. These include your device and App version details, install source, time zone, the purposes and listening contexts you selected during onboarding, how many days you have been active, whether you use the timer, how many times you have seen the paywall, and your subscription tier. To let us match subscription events to product analytics, we also send the Google Analytics app-instance identifier to the same provider.

1.4 Advertising Attribution

We measure which advertising campaigns lead to installs. We do not use this to build a profile of you across other companies' apps or websites.

  • Apple platforms. With Apple's Ad Services framework, the App requests a short-lived attribution token from the operating system and passes it to our subscription provider, which exchanges it with Apple for campaign-level information about an Apple Search Ads click. Apple provides this at a campaign level and does not require the App Tracking Transparency permission.
  • Android. Where Google Play reports that your install came from a link we published, the App reads the Play install referrer once and keeps only recognised campaign parameters from it: utm_source, utm_medium, utm_campaign, utm_content, utm_term, utm_id, and advertising click identifiers such as gclid. These are stored against your installation's subscription profile as the media source, campaign, ad group, ad and keyword. Everything else in the referrer string is discarded before it leaves your device.

1.5 Audio Delivery

Sound files are streamed and cached from our audio host at coffeebrew.org rather than bundled with the App. Requesting a sound discloses your IP address and the file requested to that host, as any web request does.

1.6 Website App-Prompt Preference

When you dismiss or use the Website's app-download banner, the Website stores a first-party timestamp in your browser's local storage under slo.web.app-upsell.dismissed-at.v1. We use this value only to avoid showing the same app-download prompt again for seven days. It is not an advertising identifier and is not sent to third parties. After seven days it no longer suppresses the prompt and is removed the next time the Website checks it. You can remove it sooner by clearing site data for slonoise.com in your browser settings.

2. How We Use Your Information

We use the information we collect to:

  • Provide, maintain, and improve the App
  • Analyze usage trends and app performance
  • Diagnose crashes, playback interruptions and technical issues
  • Serve advertisements, including personalized advertisements where you have consented
  • Measure which advertising campaigns bring people to the App
  • Manage subscriptions and in-app purchases
  • Respond to feedback and support requests
  • Comply with legal obligations

We do not sell your personal information, and we do not use the data described here to build advertising profiles of you across other companies' apps and websites.

3. Third-Party Service Providers

We share information with the following third-party service providers, each of which maintains its own privacy policy:

Provider Purpose Data Shared
Google Analytics for Firebase App analytics Usage events, device info, app version, installation identifiers, approximate location from IP
Firebase Crashlytics (Google) Crash and stability reporting Crash logs, device info, app state, installation identifier
Google AdMob and Google User Messaging Platform Advertising and advertising consent Advertising identifier (subject to consent), device info, approximate location from IP, consent choices
RevenueCat Subscription management and attribution Purchase and subscription history, device and app attributes, onboarding selections, engagement metrics, campaign and click identifiers, installation identifiers
Apple (Ad Services) Apple Search Ads attribution Attribution token exchanged for campaign-level install data
Google Play (Install Referrer) Android install attribution Campaign parameters and click identifiers attached to the install
Telegram Delivery of in-app feedback to our team Everything described in section 1.1, including any email address you provide
Tally App Store support form Whatever you enter in that form
Featurebase Feature-request portal Whatever you enter in that portal

Feedback you send through the in-app form travels over an encrypted connection to our own server, which passes it straight into a private Telegram channel that our team reads. Our server does not store a copy. Telegram is therefore a recipient of that message and of any email address in it.

Links to third-party privacy policies:

  • Google Privacy Policy (Firebase, AdMob, Google Play)
  • RevenueCat Privacy Policy
  • Apple Privacy Policy
  • Telegram Privacy Policy
  • Tally Privacy Policy
  • Featurebase Privacy Policy

4. Data Retention and Deletion

We retain your information only for as long as necessary to fulfill the purposes described in this policy, or as required by law.

Data Type Retention Period
Analytics data (Firebase) Up to 26 months from collection, under our providers' retention settings
Crash reports (Crashlytics) 90 days
Purchase and subscription records For as long as the subscription is active, plus any period required by applicable tax or commercial law
Subscription profile attributes and campaign attribution For as long as the installation's subscription profile exists, unless you ask us to delete it
Feedback and support messages Held in our private support channel until we delete them; we remove messages older than 12 months, and sooner on request
Advertising consent records Until you withdraw consent or uninstall the App
Locally stored preferences Until you uninstall the App or clear app data
Website app-prompt dismissal timestamp Seven days for prompt suppression; removed on the next Website check after expiry, or sooner when you clear slonoise.com site data

When data is no longer needed, it is deleted or anonymized in accordance with our service providers' retention schedules.

4.1 How to Delete Your Data

Because the App has no accounts, deleting your local data and deleting the data held by our providers are two separate things.

  • Data on your device. Uninstalling the App, or clearing its storage from your device settings, removes your favourites, mixes, volume settings, preferences and cached audio. It does not remove anything already sent to our providers.
  • Data held by us and our providers. Email support@slonoise.com with the subject "Delete my data" and include your installation identifier. You will find it in the App under Settings, where it appears as a name-and-number code such as SleepyCloud_1750000000000; tap it to copy. Without that identifier we have no way to find your records, because nothing else connects them to you. We may ask you for one further detail, such as the approximate date you installed the App, to locate records held under a second internal identifier.

We will confirm receipt and complete the deletion within 30 days. Deletion covers your subscription profile and its attributes, your analytics and crash records where our providers support identifier-level deletion, and any feedback messages you have sent. It cannot cover purchase records we are required to keep for tax and accounting purposes, or receipts held by Apple and Google, who act as the merchants of record. Deleting this data does not cancel a subscription; cancel it through the App Store or Google Play.

5. Advertising and Your Choices

The App displays advertisements through Google AdMob, and offers an ad-free experience through a paid subscription. Some optional content can be unlocked by watching a rewarded ad instead of subscribing.

  • EEA/UK/Switzerland users: We use Google's User Messaging Platform (UMP) to ask for your consent before serving personalized ads, in accordance with the GDPR and ePrivacy Directive. The App does not request ads until UMP reports that it may.
  • iOS users: We request your permission through Apple's App Tracking Transparency framework before your IDFA is used for ad personalization. If you decline, ads still appear but are not personalized using that identifier.
  • Android users: You can reset or delete your advertising ID from your device's Google settings at any time.
  • All users: Ads are not shown during the first 3 days after installation.
  • Ad content: We instruct Google to serve only ads rated PG or below. We do not set child-directed or under-age-of-consent flags on our ad requests, because the App is not directed at children (see section 8).

To change your advertising consent after your first answer, use your device's privacy settings, or contact us at support@slonoise.com and we will tell you how to reset it on your platform. To remove ads entirely, subscribe to Slo Premium.

6. Your Rights Under the GDPR (EEA/UK Users)

If you are located in the European Economic Area, the United Kingdom, or Switzerland, you have the following rights under the General Data Protection Regulation (GDPR):

  • Right of access: Request a copy of the personal data we hold about you.
  • Right to rectification: Request correction of inaccurate data.
  • Right to erasure: Request deletion of your personal data.
  • Right to restrict processing: Request that we limit how we use your data.
  • Right to data portability: Request your data in a structured, machine-readable format.
  • Right to object: Object to processing based on legitimate interests, including profiling.
  • Right to withdraw consent: Withdraw consent at any time where processing is based on consent.

Legal basis for processing: We rely on your consent for advertising identifiers and personalized advertising; on our legitimate interests in understanding how the App is used, diagnosing crashes and interrupted playback, and measuring which advertising campaigns work; and on the performance of a contract for subscriptions and in-app purchases. Where you send us feedback, we process it on the basis of your request.

To exercise any of these rights, contact us using the details in section 13, and include your installation identifier as described in section 4.1 so we can locate your records. We will respond within 30 days.

7. Your Rights Under the CCPA/CPRA (California Residents)

If you are a California resident, you have additional rights under the California Consumer Privacy Act (CCPA) and California Privacy Rights Act (CPRA):

  • Right to know: Request details about the categories and specific pieces of personal information we have collected.
  • Right to delete: Request deletion of your personal information.
  • Right to correct: Request correction of inaccurate personal information.
  • Right to opt out of sale or sharing: We do not sell your personal information for money. We do disclose your advertising identifier and app-usage signals to Google for advertising, which California law treats as "sharing" for cross-context behavioral advertising. You can stop it in three ways: turn on "Limit Ad Tracking" or decline App Tracking Transparency on iOS, reset or delete your advertising ID in Android's Google settings, or subscribe to Slo Premium, which removes ads. If none of those work for you, email us and we will help.
  • Right to non-discrimination: We will not discriminate against you for exercising your privacy rights.

To exercise your rights, contact us using the details in section 13 and include your installation identifier as described in section 4.1. We will respond within 45 days.

8. Children's Privacy

The App is not directed at children under the age of 13, or under 16 in the EEA where local law sets that age. We do not knowingly collect personally identifiable information from children under these ages. If we become aware that we have collected personal data from a child without parental consent, we will take steps to delete that information promptly. If you believe a child has provided us with personal data, please contact us and we will remove it.

The App's store age rating reflects the fact that its content — ambient sound — is suitable for all audiences. That rating is about content, not about who the App is intended for, and it does not make the App a children's app or place it in either store's kids category.

9. Data Security

We implement appropriate technical and organizational measures to protect your information, including encryption in transit and at rest where applicable. However, no method of electronic transmission or storage is completely secure, and we cannot guarantee absolute security.

10. International Data Transfers

Your information may be transferred to and processed in countries other than your country of residence, including the United States. The third-party service providers listed in section 3 maintain safeguards for international data transfers, including Standard Contractual Clauses or the EU-US Data Privacy Framework where these apply.

11. Data Shared with Apple and Google

By using the App, you acknowledge that Apple (for iOS/macOS) and Google (for Android) may collect data in accordance with their respective privacy policies. If you request a refund, your consumption data may be shared with the platform provider to process the request.

12. Changes to This Privacy Policy

We may update this Privacy Policy from time to time. We will notify you of material changes by posting the updated policy in the App or on this page with a revised "Last updated" date. Your continued use of the App after changes constitutes acceptance of the updated policy.

13. Contact Us

The data controller for the processing described in this policy is:

Filip Kowalski, trading as Slo
c/o Coworking Minds
Carrer Ferrers 1
07510 Sineu
Islas Baleares, Spain

If you have questions about this Privacy Policy, wish to exercise your privacy rights, or have a complaint, please contact us:

  • Email: support@slonoise.com
  • iOS support: App Store page
  • Android support: Google Play page

If you are in the EEA and are not satisfied with our response, you have the right to lodge a complaint with your local data protection authority. Our lead supervisory authority is the Spanish Agencia Española de Protección de Datos (AEPD), aepd.es.

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