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Privacy Policy

Sleep Calc Privacy PolicyLast updated: 30 September 2026Sleep Calc is an independent app developed by Kai Oelfke. For privacy questions, contact [email protected].What stays on your devicesSleep Calc stores your calculator preferences and alarm settings on your device. Some preferences sync between your iPhone and paired Apple Watch. Sleep Calc has no accounts and does not operate its own server.If you allow Apple Health access, Sleep Calc reads sleep data to show your sleep history, charts, and scores. The app processes this data on your device and does not upload your Health sleep records or write to Apple Health. You can change Health access in your device's Settings at any time.If you create alarms, Sleep Calc uses Apple's AlarmKit to schedule them and keeps their settings locally. You can remove alarms in the app or change Alarm permission in your device's Settings.Purchases and paywallsSleep Calc uses Superwall to show paywalls and manage access to paid features. Superwall assigns an anonymous app user ID and may receive device and app details, paywall interaction events, and purchase or subscription status. Sleep Calc uses this information to offer paid features and understand whether paywalls and purchases work. Sleep Calc does not send your Apple Health sleep records to Superwall. Apple processes App Store payments; Sleep Calc does not receive your payment card details.Error reports and feedbackWhen an unexpected error or unusual performance condition occurs, Sleep Calc may automatically send a diagnostic report through Google Forms. A report can include an app-specific identifier stored on your device, the app version, operating system and device model, time, code location, and error message. Sleep Calc uses these reports to find and fix problems. Health-related diagnostics can include counts of sleep samples and loading times, but are not intended to include individual sleep entries. An error message can also include technical details supplied by iOS or an integrated service.If you send feedback in the app, the message and any email address you enter are sent through Google Forms. The submission also includes the app-specific identifier, app and device details, and the anonymous Superwall app user ID for purchase support. The app-specific identifier is also used in error reports, so feedback can be associated with a reported problem. The feedback form offers recent app diagnostics and has that option on by default; you can turn it off before sending. A separate full diagnostics export is shared only if you choose to share it through the iOS share sheet.Storage, deletion, and your choicesCalculator and alarm settings remain on your devices until you change them or remove the app. Health access can be revoked in device Settings. Feedback and support submissions are kept while useful for improving Sleep Calc or providing support. Technical reports are kept while useful for diagnosing reliability problems. You can request access to or deletion of information associated with your feedback by emailing [email protected]. Locating an app-specific technical report may require its identifier or other details.Superwall, Apple, and Google process information involved in their services under their own privacy policies. This page is hosted by Carrd, which may process technical information when you visit it; see Carrd's privacy policy.ChangesSleep Calc may update this policy when the app or its data practices change. The updated page will show its new date. For questions, contact [email protected].