Privacy

Quiet Letters collects anonymous product-interaction events to help shape the next version. No accounts, no advertising identifiers, no tracking, no personal data.

What we collect

The app sends anonymous product-interaction events to TelemetryDeck, a privacy-first analytics service based in Germany. Events describe what happens in the app — for example, "a daily puzzle was completed" or "the theme changed" — never who did it.

What is not collected:

• No name, email, phone number, or account — Quiet Letters has no sign-in.
• No IDFA, IDFV, or any device advertising identifier.
• No precise or coarse location.
• No contacts, photos, microphone, or any other system permission.
• No third-party advertising or ad SDKs of any kind.
• No cross-app or cross-site tracking. Events from Quiet Letters cannot be joined with data from any other app or service.

TelemetryDeck derives a daily-rotating, salted hash from device characteristics to count unique sessions. This hash is not a stable identifier — it changes daily, cannot be reversed to identify the device, and cannot be linked back to you. Under Apple's privacy framework this qualifies as Usage Data → Product Interaction, not linked to user identity, not used for tracking, used solely for App Functionality.

What stays on your device

Quiet Letters stores a few things locally so the app remembers what you were doing:

• Your settings — theme, language, audio toggles, hard-mode default, daily-reminder time
• Your gameplay statistics — games played, win rate, current and best streak, guess distribution
• Your daily-puzzle progress — so a daily isn't lost if you switch apps mid-game

This data is written to the iOS-managed user-defaults store and SwiftData database on your device. Settings and daily-puzzle progress stay on the device they were created on.

Starting in version 1.1, gameplay statistics also sync through your personal iCloud account so the same stats appear on every iPhone and iPad signed into your Apple ID. The sync uses Apple's CloudKit private database — the data is stored in your own iCloud, managed end-to-end by Apple, and is not visible to Quiet Letters or to any third party. If you are signed out of iCloud, stats stay local to the device. Deleting the app from a device removes the local copy; deleting Quiet Letters data from iCloud (Settings → Apple ID → iCloud → Manage Account Storage) removes the synced copy from every device.

System APIs the app accesses

Per Apple's required privacy manifest, Quiet Letters declares one system API category: NSPrivacyAccessedAPICategoryUserDefaults (reason CA92.1 — accessing user defaults that belong to the app itself). No other reason categories apply.

Notifications

If you enable the optional daily reminder, the app schedules one local notification through iOS. The notification is generated entirely on-device — no server is involved. You can turn it off at any time in Settings → Notifications, or via iOS Settings.

Feedback you send us

Quiet Letters has an optional Settings → Send feedback form. It is only invoked when you type a message and tap Send; nothing is transmitted otherwise. When you do send, the message is delivered to a small Cloudflare Worker run by Laurent that turns it into a private GitHub issue we can read and reply to.

Sent along with your message: app version and build number, iOS version, device model identifier (for example iPhone15,3), in-app language, current theme, and whether hard mode is on. These are shown to you in the form below the message field, so there are no surprises. No account, email address, IP address, name, advertising identifier, or analytics hash is attached — feedback is anonymous unless you choose to include identifying details in the text you type. The intake endpoint and the GitHub issue tracker are private to Laurent; nothing is shared with third parties.

Children

Quiet Letters is rated 4+ and contains no objectionable content, no chat, no user-generated content, no in-app purchases, and no advertising. It is safe for children under 13. The anonymous product-interaction events described above contain no personal data and are not used for advertising.

Changes

Version 1.1 (May 2026) added two opt-in features described above: iCloud sync for gameplay statistics (see What stays on your device) and the Send feedback form (see Feedback you send us). If a future version changes the privacy posture further (for example, opt-in advertising — currently a deferred consideration), this page will be updated and the change called out in the in-app release notes before the new version ships.

Contact

Questions about privacy: laurent@laurent.ca