Chess Best Move

Privacy

Privacy Policy

Last updated: October 9, 2026

Summary

Chess Best Move does not collect data. The app has no server of its own, no accounts, no analytics and no ads, and it sends nothing to Motomatic LLC. Screenshots are analyzed on your iPhone or iPad and are never uploaded. The only outside parties involved are Apple services that the app uses through iOS: the App Store for purchases, iCloud Photos and iCloud Keychain if you use them, and Shortcuts and Siri.

What We Do Not Collect

  • No account and no sign-in, so no name or email address.
  • No analytics, crash-reporting or advertising software, and no third-party services or software development kits. The app’s only third-party components are the Stockfish chess engine with its neural network and bundled fonts, all credited on the Source Code page. None of them makes network connections.
  • No advertising identifier, no vendor identifier, no App Tracking Transparency prompt and no tracking. The app’s privacy manifest declares no tracking and no collected data.
  • No location. When the app opens an image, it reads only the image’s pixel size and orientation from the file, not its location or other embedded metadata. For Use latest screenshot it also reads the screenshot’s creation date from your photo library, as described below.
  • No uploads. The app never sends screenshots, positions or photo identifiers anywhere. Positions and photo identifiers that the app keeps in its storage are included in your own device backups, as described under Backups.
  • No sharing. The app shares data with no company. The Apple services it uses are described below.

Photos and Screenshots

You can bring a position into the app in several ways. Each one gives the app a single image, which is analyzed on your device.

Use latest screenshot

The app asks for access to your photo library when you request your latest screenshot, either with the Allow access to your screenshots button on Home or by opening the app from a widget. Simply launching the app does not ask for access. iOS then lets you choose full access, limited access or no access. The permission prompt says: “Chess Best Move reads your most recent screenshot to find the chessboard in it. Your photos stay on your device.”

With full access, the app looks only at the single newest image marked as a screenshot, and hidden photos are excluded. While the Home screen is showing, and again when your photo library changes or the app becomes active, it reads that screenshot’s identifier, its creation date (to show, for example, “Taken 12 s ago”) and a thumbnail of about 144 pixels for the button. The full image is loaded when you request analysis with that button or a widget. When your library changes, the app looks for the newest screenshot again and does not inspect what changed.

With limited access, the app does not read your library itself. It opens Apple’s photo picker, showing screenshots, and you pick the image. With access turned off, the app offers a link to the Settings app.

If you use iCloud Photos and only an optimized copy of the screenshot is on your device, iOS may download the full image, and the small thumbnail, from iCloud Photos. That download is Apple’s service, handled by the system, and the image is not sent anywhere else.

The app never adds, edits or deletes photos. If you follow the Shortcut setup instructions, Apple’s Save to Photo Album action saves the screenshot to Recents.

Home and Lock Screen widgets open the app to analyze the latest saved screenshot. They do not capture the screen themselves. Photo access follows the same choices described above.

Choose from Photos, Paste and Drag and Drop

  • Choose from Photos opens Apple’s photo picker, which runs outside the app and needs no permission. The app receives only the photo you pick.
  • Paste works only through the system Paste button. The app never reads the clipboard on its own, which is why iOS shows no paste permission alert, and it loads only the first image offered.
  • Drag and drop, for example on iPad, loads only the image you drop, which is then handled like any other import.

Sharing an Image to the App

When you choose Chess Best Move in the share sheet, its extension places the selected image in temporary on-device storage shared with the app for the handoff. It is not uploaded.

How an Image Is Analyzed

Everything happens on your device. The app finds the board with its own image code, identifies the pieces with a Core ML model that is part of the app, and reads the board’s coordinate labels with Apple’s Vision text recognition, which runs on the device. The Stockfish 19 chess engine runs inside the app, and the position is passed to it as text in memory. The engine makes no network connections and writes no files.

Images longer than 4096 pixels on a side are scaled down while they are decoded.

Where Screenshots Are Kept

Imported screenshots and the cropped board are kept only in the app’s memory while the screens that show them are open. The app does not save a copy of these images; the share extension uses the temporary handoff storage described above. They are released when you import another image or go back to Home, and they are gone when the app is closed.

When the app goes to the background, iOS saves a snapshot of its screen for the app switcher in the app’s storage on the device, and that snapshot can show your board. This is system behavior that the app does not change. The snapshot is removed when you delete the app.

Purchases

Purchases go through Apple’s App Store using StoreKit, which iOS handles. Apple processes payments, and the app never sees your payment details. Apple’s handling of that data is covered by Apple’s Privacy Policy.

The app contacts the App Store even if you never buy anything. At every launch it reads unfinished transactions, your current purchases, your transaction history and the list of products. It checks your purchases again each time the app becomes active, and it loads the products when the purchase screen or the offer for 15 Analyses opens, or when the card that offers switching to the yearly plan appears. While the app is open, it checks your purchases once more when an active subscription or its billing grace period is due to end. It also contacts Apple when you buy something, when you restore purchases (which can ask you to sign in to your Apple Account), when you open subscription management, and, for weekly subscribers or during a billing grace period, to read the subscription’s renewal status.

The app also reads Apple’s signed original app-download date to determine launch-offer eligibility, and the App Store environment to show purchase-testing controls only in sandbox installs.

From Apple, the app reads each transaction’s identifier and original identifier, the product and product type, the subscription group, the purchase, expiration and revocation dates, whether the purchase was upgraded, and the subscription’s next product and grace period end. It uses these on your device to decide whether Pro is active and how many purchased analyses you have. It stores only what is listed in the next section, and it attaches no account token or other account-linking value to purchases. Family Sharing is turned off for all purchases.

Data Stored on Your Device and in iCloud Keychain

App Preferences

The app keeps these values in its preferences on your device:

  • Your default think time, continued-search settings, automatic move-update preference, and board appearance.
  • Whether you have completed an analysis, so the Home screen can show shorter instructions.
  • The photo library identifiers of up to 50 photos you imported from your library or the photo picker, so the same screenshot is not offered as new again.
  • The App Store subscription group identifier.
  • Whether you dismissed or tapped the card that offers switching to the yearly plan.
  • A saved copy of your Pro status, so a subscriber is not treated as a free user while the App Store loads: whether Pro Lifetime is owned, the active subscription’s product and expiration date, and any billing grace period end.
  • Only while a purchase is pending, for example while it waits for approval through Ask to Buy: the position as text, the board orientation, how the side to move was chosen, how the board was brought in (recognized from a screenshot, changed in the editor, set up by hand or sent by the shortcut), the last move, the assumed castling rights and the time it was saved. No image is saved. The position is used for up to 24 hours. It is removed the next time you import an image or go back to Home, when its analysis starts after the purchase goes through, when a purchase update arrives more than 24 hours after it was saved, or when you delete the app. If the purchase is declined or never completes, it can stay in preferences past 24 hours until one of those happens.

Keychain Item on This Device

One Keychain item is not synced and stays on your device, apart from backups. It holds:

  • The number of free analyses left, from 0 to 3.
  • Up to 20 analyzed boards: the piece placement of each position an analysis was used on, or that was analyzed while Pro was active, stored as 64 characters of text. No image is stored.
  • When the offer for 15 Analyses was last closed without buying.
  • A random device identifier that the app generates. It is not a hardware identifier or an advertising identifier.
  • This device’s copy of the purchased-analyses record described next.

This item is kept in the Keychain so that deleting and reinstalling the app does not reset the free analyses.

Keychain Item Synced through iCloud Keychain

If you buy 15 Analyses, a second Keychain item is created and marked for syncing. If you never buy it, this item does not exist. If you have iCloud Keychain turned on, Apple syncs it to your other devices signed in to the same Apple Account, so 15 Analyses bought on one device can be used on all of them. It holds:

  • A format version number.
  • The number of pack analyses used on each device, listed by the random device identifier.
  • The App Store transaction identifiers of packs already added to your balance, and of packs that were refunded or revoked.
  • The number of analyses written off after a refund.

It contains no name, email address, Apple Account identifier or payment information. Motomatic LLC cannot read your iCloud Keychain.

Launch Access in iCloud Keychain

A separate Keychain item stores your launch-offer eligibility, Apple’s verified original app-download date, and the offer cutoff. It is marked for syncing through iCloud Keychain so your access can follow the same Apple Account, and it lets an eligible download keep unlimited access offline. Motomatic LLC cannot read it.

Backups

The app’s preferences, including the photo identifiers and any position saved while a purchase is pending, are included in iCloud and computer backups by default. The device-only Keychain item, including its analyzed boards, is included in iCloud backups and encrypted computer backups, and can move to a new device through them or through a device-to-device transfer. These backups belong to you. None of this is sent to Motomatic LLC.

App Shortcuts

The Find Best Move App Shortcut takes an image that the Shortcuts app passes to it, usually from the Take Screenshot action. It opens Chess Best Move, decodes the image in memory and analyzes it on your device like any other import. It then returns a short text result to Shortcuts, such as “Best move: knight to f3. White is ahead by 0.4 pawns.”, which Siri may speak. The app does not store the image.

Apple Services and Links

The app contains no networking code of its own. The only outside parties are Apple services, used through iOS:

  • The App Store and StoreKit, for purchases, restoring purchases and subscription status.
  • iCloud Photos, for downloading a screenshot’s original when only an optimized copy is on your device.
  • iCloud Keychain, for syncing purchased analyses and launch-offer eligibility when you have iCloud Keychain turned on.
  • Shortcuts and Siri, for running the App Shortcut and speaking its result.

Data handled by these services is covered by Apple’s Privacy Policy. The app shares data with no other company.

Some buttons open a web page in your browser or open a system app. The app itself does not load these pages. They are this privacy policy, the terms of use, the Stockfish source code on GitHub, the source code of the app, the Leela Chess Zero training data page and the Open Database License text. The app also opens the Settings app, to change photo access, and the Shortcuts app.

System Log and Device Information

When something goes wrong with purchases or the analysis count, the app writes an error message to Apple’s system log on your device. These messages can include App Store product and transaction identifiers, random identifiers created for each analysis, Keychain error codes and error descriptions. They never include images, positions or photo identifiers. The log stays on your device unless you share diagnostics with someone.

The app reads your device’s model identifier, to name the right buttons in its screenshot instructions, and the device’s memory and number of performance cores, to size the chess engine. These values are used only on the device. They are not stored or sent.

If you choose to share analytics with app developers in your device’s settings, Apple can make crash logs and App Analytics available to developers through App Store Connect and Xcode. Apple collects that information; the app does not send it.

Children

The app has no accounts, collects no personal information and has no features aimed at children. When a purchase needs approval, for example through Ask to Buy, the app keeps only the position in its preferences while it waits, as described under App preferences.

Your Choices and Deleting Data

  • Photo library access is used for Use latest screenshot and widgets that request the latest saved screenshot. Choose from Photos, Paste and drag and drop work without it, and you can change photo access at any time in the Settings app.
  • Whether purchased analyses and launch eligibility sync depends on your iCloud Keychain setting.
  • Deleting the app removes everything in its storage: the preferences listed above (think time, photo identifiers, saved Pro status and any position saved while a purchase is pending) and anything iOS cached for the app. Backups made before you deleted the app keep their copies.
  • The Keychain items remain after the app is deleted. The purchased-analyses record is created only if you buy 15 Analyses; launch eligibility is stored separately. This is intended, so that reinstalling does not reset the free analyses or the record of analyzed boards. Synced records can also remain in iCloud Keychain and on your other devices. The app has no setting that erases the Keychain items. Erasing your device removes the device-only item.
  • The app never changes your photos. Your purchases and transaction history stay with Apple.
  • The app sends nothing to Motomatic LLC, so there is no app data to delete on our side. Apple gives developers App Store sales reports and, only if you chose to share analytics with app developers, crash logs and App Analytics. Apple does not include your name or Apple Account in them.
  • To have your support emails deleted, email support@motomatic.com.

This Website and Email

This website uses no cookies, analytics or trackers, and it loads nothing from other sites. It is hosted on GitHub Pages. GitHub’s documentation says: “When a GitHub Pages site is visited, the visitor’s IP address is logged and stored for security purposes, regardless of whether the visitor has signed into GitHub or not.”

If you email support@motomatic.com, Motomatic LLC receives your message, your email address and anything you attach. Email is separate from the app. We use your email only to answer you and do not share it with anyone else, apart from the email service that hosts our mailbox, and we delete your emails on request.

Changes to This Policy

If the way the app handles data changes, we will update this page and the “Last updated” date above.

Contact

Questions about this policy or about how the app handles data? Email support@motomatic.com. Chess Best Move is made by Motomatic LLC.