Privacy Policy

Last updated: 10 September 2026

One Letter is operated by Fan Qu. This policy explains how One Letter handles information when you use the app and its letter, community-board, and conversation features.

Information we handle

We process the account information supplied by Apple, Google, or your email sign-in; profile settings you choose; letters, replies, and saved drafts; safety reports and blocks; and device notification tokens if you choose to enable notifications. We use a service account identifier to keep your content available across your signed-in devices.

Why we use it

We use this information to authenticate you, deliver letters and conversations, protect the community, maintain your account, and respond to support requests. We do not sell personal information or use it for cross-app advertising tracking.

Service providers

One Letter uses Firebase and Google services to provide authentication, database, cloud-function, notification, and hosting capabilities. Apple and Google provide the sign-in method you select. These providers process information only to provide their services to us.

Community safety

Daily-board notes are public. A reply to a system-generated prompt may also become a community letter for another user. A direct conversation with another user is private to its participants and is not placed in the community pool. Drafts are stored on the device; saved self-letters and conversation records may be synced to your account. Time capsules are a delayed-opening feature, not end-to-end encryption.

Letters and replies can be reported, removed from your view, or associated with a blocked sender. We use those reports to investigate misuse and enforce our community rules. Do not include private contact details, passwords, financial information, or other sensitive information in letters.

Retention and deletion

We retain account information and content while your account is active. You can permanently delete your account from My Corner in the app. When deletion succeeds, we remove your account, letters, replies, blocks, and synced records. We may retain the minimum safety or legal record necessary to address abuse, fraud, or legal obligations.

Your choices

You may choose which sign-in method to use, disable notifications in your device settings, report or block content, and delete your account. For access, correction, or privacy questions, contact us at qufan688@gmail.com.

Children

One Letter is not directed to children under 13. Do not use the app if you are under 13.

Changes

We may update this policy when the service changes. The current version and its update date will always appear on this page.