Privacy Policy
Tempo Chess Diary
This policy explains how this application handles information and how to contact us about privacy.
Information we process
Tempo Chess Diary stores the games you record, dates, opponent names you choose to enter, piece colors, outcomes, opening names, PGN moves, notes, quality ratings, your personal opening and endgame library, mastery history, training plans, task completion, reminder dates and optional local player name on your iPhone. A random installation secret is held in the iOS Keychain. Sync is optional and off initially. When enabled, the app sends an AES-GCM encrypted diary snapshot, its revision and an installation authorization secret over HTTPS. The backend stores the encrypted snapshot, a SHA-256 hash identifying the installation, a revision and the update time in PostgreSQL. It does not store the plaintext installation secret. Hosting infrastructure receives network metadata such as IP addresses, request paths, timestamps and response status when the app syncs or you visit this public website. There are no accounts, analytics SDKs, advertising SDKs or tracking cookies.
How we use information
Local data powers the diary, keyword-based reflection analysis, personal repertoire, training planner and progress statistics. Reminders use local iOS notifications. Optional encrypted sync keeps the latest snapshot for this installation; it is not an account or a cross-device recovery service. Authorization hashes isolate installations, and revisions prevent stale snapshots from silently overwriting newer data. Operational error logs use request identifiers and generic error codes to diagnose availability without deliberately logging diary contents or authorization headers. PGN imports are read locally; exports are passed to the iOS share sheet only when you request them.
Service providers and sharing
The backend and PostgreSQL database are hosted by Railway, which processes encrypted snapshots and technical request information as hosting infrastructure. The app has no third-party analytics, advertising, email delivery or chess-platform integration. We do not sell diary data. The iOS share sheet sends the PGN file to a destination you select; that destination handles the file under its own practices. Apple provides the operating system, Keychain, local notifications and any device backup you configure. Infrastructure providers may process operational logs to run and secure the service. Data may be disclosed if legally required.
Data retention
The local diary stays on your device until you delete it or remove the app, subject to any device backups you have configured. The installation key may remain in Keychain after app removal and is restricted to this device. The server keeps the latest encrypted snapshot until it is replaced or you request deletion for that installation; there is no application-level snapshot history or scheduled expiry. We have not configured a specific infrastructure log or provider backup retention period and do not promise immediate removal from provider-managed backups. Any retained backup copies remain subject to the hosting provider's lifecycle rather than being immediately rewritten by an application deletion. App-created PGN files may also remain temporarily in the app cache until cleared by the system or the app data-deletion control.
Deleting your information
Settings includes Delete all diary data. Deletion pauses sync immediately. If a sync installation key exists, the app first requests server deletion and only clears the local diary after the server confirms success; if offline or the request fails, it keeps local data and explains that deletion must be retried. Successful deletion removes the active database snapshot, local diary and pending local reminders and disables sync. App-created temporary PGN exports are also removed; copies already shared elsewhere are not. The installation key remains in Keychain. Individual games, library entries and plans can also be deleted in the app; enabled sync replaces the server snapshot with the updated diary. Deleting an exported PGN or copies held by a recipient is your responsibility. Removing the app alone does not send a server deletion request. We cannot identify or recover an encrypted snapshot for you after loss of the installation key.
Permissions and your choices
Notifications are requested only when you save a training reminder. You may decline or revoke notification permission in iPhone Settings; the diary continues to work. Reminders run locally and are not push notifications. You choose PGN files through the system file picker and choose export destinations through the share sheet. The app does not request location, contacts, microphone, camera or photo-library access. Optional sync can be disabled in app Settings; disabling it stops future automatic sync but does not delete a previously saved server snapshot.
Your privacy rights
You can view and edit your records, export games in PGN, disable optional sync and request deletion through Settings. For privacy questions or applicable access, correction, deletion or objection requests, contact hamish.cavendish@icloud.com. This is a public privacy contact, not an in-app messaging or account system. Depending on where you live, you may also have rights to complain to a data protection authority. Because no account is collected and the server stores encrypted content under an installation hash, we may be unable to locate or decrypt a particular installation's data without its device-controlled authorization. Do not email your installation secret.
Security
The app uses iOS file protection for local diary files, Keychain storage with a device-only accessibility class for the random installation secret, AES-GCM authenticated encryption for sync snapshots and HTTPS for transport. The encryption key is derived from the installation secret. The backend verifies installation-scoped Bearer authorization, stores only the secret hash, validates request sizes and fields, uses parameterized database queries and rejects conflicting revisions. Anyone who obtains the installation secret could access that installation's snapshot; keep your device secure. No storage or transmission method can be guaranteed completely secure. The encryption key is derived from the same secret used for server authorization. The server receives that authorization secret during requests but does not deliberately retain it. This protects stored snapshots, and is not a promise that the hosting infrastructure could never decrypt a request it observes.
Children’s privacy
Tempo Chess Diary is a general-purpose chess study utility and is not specifically directed to children. It has no accounts, social messaging or advertising. A child using the app should avoid putting personal information about themselves or others in notes or opponent fields and should use sharing and optional sync with an appropriate adult's guidance. Contact hamish.cavendish@icloud.com with concerns about a child's data.
Changes to this policy
This policy describes the released app and its backend as of the effective date above. If processing changes, we will update this page and its effective date, and update in-app information when needed. Review the Privacy Policy link in Settings for the current text. Material changes requiring a choice will be reflected in the relevant app controls before that processing is enabled.