Your questions are for rulings, not advertising.

Information processed

The app creates a random installation identifier. The server stores only a one-way hash of that identifier and uses it to apply the daily question limit.

When you ask a question, the service stores the question, generated answer, cited rules, referenced cards, model name, confidence, client platform, and request time. If you send feedback, the verdict and optional note are stored with that answer.

Deck names, commander names, and card lists saved in Deck Coach remain in app-local storage on the Android device, including up to 20 saved versions per deck. When you tap Analyze, the service processes the deck transiently against its card catalog; analysis does not store the deck in the application database or question-review log and does not send it to the AI service provider.

If optional Google accounts are enabled and you choose to sign in, Google provides a verified account identifier, verified email when available, display name, and profile image address. The server creates an installation-bound session and stores only its hash. You can continue using the app anonymously.

When signed in, Back up explicitly uploads a deck name, commander selections, and card list to your account. Up to 20 decks and the latest 20 backed-up versions per deck are retained. Backups do not include card artwork, card databases, or AI analysis, and are not sent to an AI provider. There is no automatic upload. Hosting, networking, and security providers may process technical request metadata under their own retention policies.

Cards search sends the entered card-name query to the public Spellbook Judge catalog route. Opening card details requests that card's public data from Scryfall. These requests do not include your account session, installation token or saved deck list and do not call the AI provider. Hosting and network providers may process ordinary technical request metadata.

The opening-hand simulator shuffles and draws from a saved deck on your device. It does not upload your deck or simulated hand, change the saved list or use an AI question. The separate Analyze action can load card metadata, and displayed artwork may still require a network request.

When Cards, Deck Coach or the opening-hand simulator displays card artwork, the app loads that public image directly from Scryfall's image CDN. Like an ordinary web image request, Scryfall may receive the requested image address and standard network metadata such as the device's IP address and user-agent information under Scryfall's own privacy practices. Spellbook Judge does not add the deck name, full deck list, rules question, or anonymous installation token to the image request.

The hosting platform may provide a coarse edge-routing code for operational analytics. Spellbook Judge does not request GPS access and does not intentionally store raw IP addresses in product analytics.

How information is used

Information is used to provide rules answers, enforce beta limits, diagnose failures, understand aggregate usage, and improve answer quality through reviewed feedback. Deck Coach analysis returns deterministic card, legality, structure, and synergy checks. Separately requested account backups let you recover saved deck versions on another installation. Information is not used for targeted advertising.

Service providers

Rules questions and retrieved evidence are processed by an AI service provider to generate explanations. Deck Coach's deterministic analysis does not send deck content to that provider. Scryfall provides card data and serves card artwork requested by the app. Hosting and database providers process the technical data needed to operate the service. Providers act under their own security and privacy terms.

Retention and deletion

Beta questions, answers, and feedback are retained in active storage for no longer than 12 months. Daily usage rows normally expire after 32 days; stale anonymous installations and legacy user rows without account storage expire after no more than 12 months. Accounts with backup storage remain until you delete the account. Service-provider logs and backups can follow separate schedules.

Locally saved decks remain on the Android device until you delete them or clear the app's local data. Deck content submitted for analysis has no application-database or question-log retention because it is processed transiently.

Cloud backups remain when you sign out or delete one installation's data. You can export your account in Android after verifying your Google account. To permanently remove all cloud deck versions, your account profile, and account-owned question history across devices, choose Delete account and cloud data in the account panel, or use the account deletion page without the app. Recent verification of the same Google account is required. Local deck copies are kept unless you separately delete them. Today's numeric question count is kept until its normal reset.

After account deletion, a one-way fingerprint of the Google account identifier and the deletion time block already-started sign-ins from recreating that account. This contains no email, profile or deck content. The protection expires after ten minutes and the marker is removed by scheduled cleanup, normally within the following minute while accounts are enabled. A new sign-in started after deletion can create a fresh empty account.

Use Delete my data in the updated Android or web app to remove that installation’s saved questions, feedback, usage records, and account link from active storage. The app then creates a new anonymous installation identifier. In this supported flow, only today’s numeric question count is carried to the new identifier until the next UTC reset; no question or answer content is carried with it. Because use is anonymous, clearing app/browser storage, reinstalling, or using an older client can create an unrelated identifier; service-wide limits remain in place as a cost backstop.

To prevent a deleted installation identifier from silently recreating data, the service indefinitely keeps only a 32-byte, domain-separated one-way fingerprint and the deletion time. This suppression record contains no raw installation token, device ID, account information, question, answer, or feedback. If the deleted identifier is sent again, the server requires the app to create a new anonymous identifier. Earlier anonymous or legacy questions are not retroactively assigned to a Google account; they remain covered by installation deletion and the retention limit above. Google accounts and backups are available only in builds and servers explicitly configured to enable them.

Privacy help: Email spellbookjudgesupport@gmail.com.

Children and security

Spellbook Judge is not directed to children and does not knowingly collect personal information from children. Reasonable technical measures protect stored information, but no online service can guarantee absolute security.

Attribution and independent status

Spellbook Judge is an unofficial fan-made companion. It is not approved, sponsored, endorsed, or affiliated with Wizards of the Coast.

Magic: The Gathering, card images, mana symbols, and related Wizards materials are property of Wizards of the Coast LLC. © Wizards of the Coast LLC. Card data and image links are provided through Scryfall; neither Wizards nor Scryfall endorses this app.

Last updated September 14, 2026.