Privacy Policy

This policy applies to the PIYOKEY iOS and Android apps, the web service officially available at piyokey.com, typee.app, and through ChatGPT, and the related privacy and support pages. “Operator” means the developer and provider of PIYOKEY.

The iOS and Android apps have no Piyokey account or advertising SDK. Even if you enable usage analytics or crash diagnostics, the apps do not send:

• names, email addresses, phone numbers, or other contact information;
• typed text, answers, searches, or raw learning history and progress;
• user-deck names or content, photos, microphone audio, or recordings;
• advertising IDs, precise location, contacts, or activity across other companies’ apps and websites; or
• session replays or automatically captured screens and interactions.

Apple and Google process information under their own policies only when you choose the optional store or leaderboard features described below.

Practice and game records, streaks, downloaded decks, review items, display, sound and keyboard preferences, Piyo customization data, and the last confirmed Deck Maker entitlement are stored locally. They are used only to provide features and resume your learning, and are not sent to the operator’s servers.

A .piyodeck file you select is validated and stored on your device and is not uploaded to Piyokey. Deleting the app removes its local data, so export any user decks you need first. Exported files remain at the destination you selected.

Usage analytics and crash diagnostics are both off until you make the first privacy choice. “Participate and continue” turns both on; “Continue without sharing” leaves both off. Every lesson, game, and purchased feature remains available either way. You can change the two settings independently at any time.

Usage analytics (PostHog Cloud EU)

When enabled, the app sends app opens; categories of features and settings used; onboarding; deck source and category; practice and game starts and outcomes; bucketed duration, item-count, and score ranges; purchase-flow state; app and build version; operating-system family; display language; and a random app identifier. It uses predefined categories and ranges rather than exact typed content or a continuous learning history.

Crash diagnostics (Firebase Crashlytics)

When enabled, the app sends crash logs, relevant app state such as the feature or mode active at the time, general device and operating-system information, and a random installation identifier. Turning it off deletes unsent diagnostic reports and stops future collection.

We use this information only to improve quality and diagnose faults, not for advertising, IDFA, or tracking across other companies’ services.

PostHog Privacy Policy · Google Firebase Privacy and Security

Only after consent to the updated usage analytics notice, PostHog Cloud EU also processes device model and type, OS version, screen dimensions, app distribution environment, device language and time zone, Wi-Fi or cellular connection type, and a random session identifier. Existing users choose usage analytics again; their diagnostic choice is preserved. Declining does not restrict app features.

We record only the country name and code inferred from the connection IP. The IP is processed temporarily for this inference and is not stored with events. We do not retain region, state, city, postcode, coordinates, accuracy radius or an IP-derived time zone, and do not collect GPS location or user-assigned device names. Device time zone means the device setting, not IP-derived location. VPNs and network routing can make the country inaccurate; it does not establish residence.

The production PostHog project follows its free plan’s one-year event retention period. Firebase Crashlytics processes data on Google’s global infrastructure; removal of crash data and associated identifiers from live and backup systems begins after 90 days.

Turning sharing off in Settings stops new transmission, but does not immediately erase records already sent; those follow the retention periods above. Request deletion through support. Without accounts and with random identifiers, we may be unable to identify your records. We will explain when this applies and use processor deletion tools for records we can identify.

PostHog · Firebase

The web service stores language, display, sound and keyboard preferences, local XP, learning totals, selected decks, tutorial status, and personal bests in your browser’s local storage. The language preference cookie lasts for up to one year. This information remains in the browser except for the server features described below.

When you start or complete a practice session or use ranked play, the service issues a random guest identifier for that browser. The guest cookie is HttpOnly and SameSite-protected and lasts for up to 180 days; the server stores its hash. To calculate popular decks, we record the date, deck, entry source, and start or completion counts. For ranked play, we record the mode, deck, course, start and finish times, score, accuracy, combo, duration, correct and attempted key counts, correct-answer and miss counts, and a digest of the input event sequence. To validate the result, an event sequence containing each correctly entered Hangul jamo and its relative input time is sent temporarily, but the raw sequence is not stored. The actual keys entered for mistakes are not sent. Your leaderboard name and ranked result are visible on the leaderboard.

If you use optional sign-in on the ChatGPT-hosted version, we use the email address and full name supplied by OpenAI or ChatGPT to show sign-in state and turn the email address into a hashed account key. The ranking database does not store the email address or full name itself. We use this information for browser continuity, aggregate deck popularity, leaderboards, fair-play checks, and abuse prevention. We retain it while needed for ranking history and service operation, or until we fulfill a deletion request. Depending on the deployment, Vercel or Cloudflare delivers the web service, and Turso or Cloudflare D1 stores ranking and practice records.

Turso Privacy Policy

Leaderboards and achievements (optional)

Only when you explicitly choose them, Game Center on iOS or Google Play Games on Android processes scores, achievement progress, and profile display information. The operator does not receive Apple Account or Google Account credentials or store them in a separate user database.

Apple: Game Center & Privacy · Google Privacy Policy

Deck Maker purchase (optional)

The App Store on iOS or Google Play on Android processes product information, purchases, payment, and refunds. The app applies the purchase status returned by the store to an entitlement stored on your device. The operator does not receive card details or store passwords and does not run a separate purchase or receipt server. App Store and Google Play purchases do not transfer between stores.

Google Play Terms of Service

Notifications (optional)

Piyokey asks for OS notification permission only if you enable a daily reminder. Reminder settings and scheduling are handled on your device; Piyokey does not use remote push notifications.

Pronunciation, files, and sharing

Pronunciation uses bundled audio or on-device Korean speech synthesis, and the app does not record or transmit microphone audio. File pickers, export, and sharing open only when you choose them. The selected storage or sharing destination’s policy then applies.

When you access the web service, or when a mobile app retrieves an online read-only catalog or learning deck, delivery infrastructure such as Vercel or Cloudflare may temporarily process network information needed to deliver and secure the request, including IP address, request time and route, and general device or browser information. It is used to deliver the service or content, maintain security, and prevent abuse, not for advertising.

Except for ranked-result validation described above, typed text, learning history, and store or leaderboard credentials are not sent to the content host.

The Vercel-hosted web service uses Vercel Web Analytics to measure aggregate page usage and improve the service. The current configuration measures page views only. It does not send custom events, typed text, answers, or learning history.

For each page view, Vercel may process the date and time, page or route, referrer, filtered query parameters, approximate location (country, region, and city), and general browser, operating system, and device type information. Vercel Web Analytics does not use cookies to identify visitors. A request-derived hash resets daily, and the visitor session is discarded after 24 hours. Analytics data is not linked to a person or IP address and is not used to track a visitor across days or websites. This analytics service is not included in the mobile apps or the Cloudflare-hosted web version. Reporting availability and retention depend on the Vercel plan, and Vercel may store data beyond the guaranteed reporting window.

Vercel: Web Analytics Privacy and Compliance · Vercel: Web Analytics Limits and Retention

If you contact support, we may receive your email address, message, and any information you choose to attach. We use it only to answer the request, protect the service, and resolve similar issues. We retain it no longer than needed for the response and legal obligations. You may ask for deletion through the support page.

• Usage analytics and crash diagnostics: turn each setting on or off at any time in the app. Turning it off stops future transmission.
• Notifications: turn them off at any time in the app or OS notification settings.
• Game Center and Google Play Games: sign out or change visibility in the relevant OS or service settings.
• On-device data: export any user decks you need, then delete the app to erase its local data.
• Store purchase history: manage it through your Apple or Google store account.
• Web browser data: clear cookies and site data in your browser.
• Web guest, ranking, and support information: ask support to delete it.

The mobile apps do not track activity across other companies’ apps or websites. They do not request App Tracking Transparency permission on iOS or the advertising ID on Android.

We use HTTPS for necessary network traffic and minimize the information handled. We do not sell personal information. Information received through support is not shared except when required by law.

PostHog Cloud EU and Google Firebase Crashlytics process mobile analytics and diagnostics that you choose to share on the operator’s behalf. Apple’s and Google’s privacy policies apply to processing by their features. Depending on the deployment, Vercel or Cloudflare processes web and static-content delivery, and Turso or Cloudflare D1 processes web ranking and practice record storage. Vercel also provides aggregate analytics on the Vercel-hosted version. OpenAI or ChatGPT is involved when you choose optional sign-in on the ChatGPT-hosted version.

PostHog Privacy Policy · Google Firebase Privacy and Security · Cloudflare Privacy Policy · Google Privacy Policy · OpenAI Privacy Policy

We may update this policy as features or laws change. Material changes will be reflected by a new date on this page and, when appropriate, an in-app notice.

For privacy, deletion, or other Piyokey questions, visit the support page or email contact@typee.app.