Privacy
policy

Last updated: 25 September 2026 · Applies to: CardSync for Google Photos

CardSync is a macOS app that copies photos and videos from a memory card to your own Google Photos library. It runs entirely on your Mac. There is no CardSync server, no CardSync account, and your photographs are never sent anywhere except to the Google Photos library you signed in to.

What CardSync can do with your Google account

CardSync asks for one Google Photos permission: https://www.googleapis.com/auth/photoslibrary.appendonly.

That permission lets an app add photos and videos to your library. It does not allow reading, browsing, altering, sharing or deleting anything already there. CardSync therefore cannot see your existing photos, and could not send them elsewhere even if it tried.

It also asks for your email address (the openid and email permissions), for one reason: so the app can show which Google account your photos are going to. The address is kept only on your Mac, is never sent to us or anyone else, and is deleted when you disconnect.

We request no other Google permission — not your profile, not your name, not your contacts, not Google Drive.

Signing in uses Google's standard OAuth flow with PKCE. The browser window that opens is Google's own, so CardSync never sees your Google password, and the redirect is caught by a temporary listener on 127.0.0.1 — nothing is exposed to your network.

What stays on your Mac

Four things are stored locally, and none of them is transmitted anywhere.

A record of files already uploaded

Content fingerprints, file sizes, capture dates and the card a file came from, kept in ~/Library/Application Support/CardSync/. This is so that re-inserting a card does not upload the same photo twice. Google's API cannot be asked what your library already contains, so the app has to remember. It holds no photographs — only the fingerprints and dates.

Your Google sign-in token

Kept in the macOS Keychain, so that you only sign in once. It is a credential and is stored as one.

The email address of the connected Google account

Kept in standard macOS app preferences, so that you can see which account photos are being uploaded to.

Preferences

Standard macOS app preferences — settings such as whether to upload automatically.

You can inspect or erase the upload record at any time from Settings → History, and disconnecting removes the stored token and the email address. Deleting the app removes all of it.

How your data is protected

Security measures are in place to protect the confidentiality of your Google user data and your photographs:

• Encryption in transit. Every connection CardSync makes — to Google for sign-in and uploads, and to Sentry for diagnostics — uses HTTPS (TLS). Nothing is sent unencrypted.
• Encrypted credential storage. Your Google sign-in (refresh) token is stored in the macOS Keychain, which encrypts it at rest and restricts it to CardSync. Short-lived access tokens are held only in memory and never written to disk.
• Least privilege. CardSync requests only the permissions described above. The Google Photos permission it holds cannot read, change or delete anything in your library.
• No central store of user data. We operate no server, so there is no database of users, tokens or photos that could be breached. Your data stays on your Mac, protected by your macOS user account and, if you have it turned on, FileVault disk encryption. The Mac App Store version additionally runs in Apple's App Sandbox, which prevents other apps from reading its data.
• Revocation on disconnect. Disconnecting in the app asks Google to revoke CardSync's access, then deletes the stored token and email address from your Mac.
• Minimised diagnostics. Diagnostic reports exclude your Google account, email address, photographs and file names, and IP address collection is switched off, as described below.

Your photographs

Photos and videos are read from your memory card and uploaded directly from your Mac to Google. They do not pass through any server of ours, because we do not operate one. Files on the card are never modified, moved or deleted. Nothing you upload is used to train anything.

Once a photo is in your Google Photos library it is governed by Google's Privacy Policy and your own Google account settings. CardSync has no further access to it.

Diagnostics

So that crashes and failures can be fixed, CardSync sends limited technical diagnostics to Sentry, an error-monitoring service acting as our data processor.

What is sent

• Crash reports, including the technical stack trace.
• Counts and timings — how many files were scanned, uploaded, already present, skipped or failed; total bytes; how long a scan or upload took.
• The app version, and whether a card was read as a mounted disk or through macOS Image Capture.

What is deliberately not sent

• Your photographs, or any part of them, including thumbnails.
• File names, folder names, file paths, or the name of your memory card.
• Photo metadata such as EXIF, camera model or serial number.
• Your Google account, email address or name.
• Your IP address — the app switches off IP collection, so it is not recorded against a report.

As a second line of defence, the app strips anything resembling a file path from diagnostic text before it is sent, in case a path reaches a crash report by accident.

Feedback you choose to send

Settings → Feedback sends exactly what you type, plus the app version, to Sentry so we can read and act on it. If you supply an email address it is used only to reply to you. Unlike diagnostics, feedback text is not filtered — it is your message, so if you mention a file name it is sent as written. Nothing is sent unless you press Send.

Who else is involved

• Google Photos receives the photos and videos you choose to upload, handled per your own Google account.
• Sentry receives crash reports, the counts above, and any feedback you send. It processes them in the United States, and that transfer relies on its standard contractual clauses.

There is no advertising, no analytics profiling, no data broker, and nothing is sold or shared for marketing.

Google API Services User Data Policy

CardSync's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. Google user data is used only to provide CardSync's upload feature and to show which account is connected. It is not used for advertising, not sold, not transferred to third parties, not read by people, and not used to develop, improve or train AI or machine-learning models.

How long things are kept

• On your Mac: until you clear the upload history, disconnect, or delete the app.
• Diagnostics and feedback: retained by Sentry under our account's retention period and then deleted automatically.
• Your photos: in your Google Photos library, under your control, for as long as you keep them.

Your rights

Under UK and EU data protection law you may ask what we hold about you, ask for it to be corrected or erased, or object to it being processed. In practice we hold very little: diagnostics carry no identifier for you, so there is usually nothing to look up unless you have sent feedback with an email address. Write to us and we will act on it.

You can revoke CardSync's access to your Google account at any time at myaccount.google.com/permissions, independently of anything in the app. Photos already uploaded stay in your library until you delete them there — CardSync cannot remove them for you, because its access is append-only.

Children

CardSync is not directed at children and we do not knowingly collect their data.

Changes

If this policy changes materially, the date at the top changes and the new version appears here; the previous version stays in the site's git history. Meaningful changes will be noted in the app's release notes.

Contact

Questions about any of this: hello@bitesizebureau.com.

See also the terms of use. CardSync is not affiliated with, endorsed by, or sponsored by Google.

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