Privacy, in plain language.

Models and printers

Models, slicing, settings, printer credentials, and local projects are handled on your device. iOS projects may also use your iCloud Drive when configured. Printer discovery, print commands, file transfers, and camera feeds go directly to a printer on your local network. WrenSlicer does not send printer passwords to its backend.

WrenSlicer Cloud

If you sign in and choose WrenSlicer Cloud, the project files you upload, their names, and sizes are stored with your account in Cloudflare R2. Local projects are not uploaded automatically. Cloud files remain available while your Max plan is active and for a 30-day grace period after it ends, then a scheduled purge removes them. You can delete a file or request account deletion. Account deletion starts cloud-file removal asynchronously, so removal may not be immediate.

Accounts and purchases

If you create an account, WrenSlicer receives the sign-in identity you choose: your email address for email-code sign-in, or an Apple or Google account identifier and any email the provider returns. The service stores an account ID, linked sign-in methods, plan or licence state, AI allowance and usage history, and hashed refresh tokens. Email codes are stored as salted hashes and expire after 10 minutes. Refresh sessions expire after 90 days without use.

Apple App Store and Google Play handle mobile purchases. Lemon Squeezy handles desktop checkout. WrenSlicer receives the purchase or licence information needed to verify the plan and provide its features; it does not receive full payment-card details.

AI features

When you choose an AI feature, your request may include a selected photo, text, part design, dimensions, material or printer details, and the answer. WrenSlicer sends this to its Cloudflare backend, which sends the content needed to Anthropic’s Claude API. The backend does not save the prompt, photo, or answer in your account record. An authenticated request can be associated with your account by WrenSlicer’s backend; the Anthropic request does not include your WrenSlicer account ID.

Under Anthropic’s standard API retention terms, API inputs and outputs are deleted within 30 days, except for policy enforcement, legal requirements, or a different written agreement. See Anthropic’s API retention terms.

Update checks on Windows and Mac

The desktop app checks for a newer version at most once a day, and when you choose Help › Check for Updates, by downloading a small public file from this website (hosted on GitHub Pages). The request carries no account, device, licence or usage information; GitHub receives your IP address and the request time, as with any web page. The app only shows a notice and opens the download page; it never installs anything by itself. You can turn the daily check off under Account › About.

Problem reports on Windows and Mac

The desktop app keeps a small problem log on your computer that records errors such as a failed slice or a crash, with the app version and the kind of computer. File locations are reduced to file names, and passwords, access codes, tokens, licence keys, email and network addresses are removed before anything is written. Models, G-code and account details are never logged. Nothing is sent automatically: Help › Report a Problem shows you the report first, then opens your own email app for you to send it. WrenSlicer uses no crash-reporting service.

Print notifications

If you enable print notifications, WrenSlicer may store a push token for your device, a hashed printer key, printer and file names, print phase and progress, and an iOS Live Activity push token. Apple Push Notification service or Firebase Cloud Messaging delivers notifications. A printer watch is removed 48 hours after its last status update, or one hour after it ends. You can remove a device or watch in the app. Printer host names and passwords are not included in the watch record.

Beta sign-ups

If you sign up for the beta on this website, WrenSlicer stores the email address, optional first name, printers, firmware, computer and phone type, and note you enter, with the time. They are kept in Cloudflare, read only by the owner to choose and contact testers, and deleted when the beta ends. Email us to remove your sign-up sooner.

Logs, tracking, and service providers

WrenSlicer does not include an advertising or analytics SDK and does not use data for cross-app tracking. Backend event logs omit fields such as email, tokens, printer names, and addresses, reduce account IDs to short hashes, and scrub error messages. Owner or developer access changes may be recorded with the staff and account IDs, action, reason, and time. Cloudflare processes connection and service metadata to operate its services. Production logging and audit-record retention settings must be confirmed before launch.

Depending on the feature, providers include Cloudflare, Anthropic, Resend, Apple, Google, Firebase Cloud Messaging, and Lemon Squeezy. Each provider handles information under its own applicable terms.

Account deletion

Use Account → Delete account in the app. Where available, the web deletion page verifies your email with a one-time code. Deletion removes your account profile, sign-in links, sessions, AI allowance and history, and cloud file index, and starts deleting cloud files. Projects and print history saved only on your device remain. If you used Sign in with Apple, the app or deletion page explains how to remove WrenSlicer from your Apple Account's Sign in with Apple settings; WrenSlicer does not currently revoke that Apple authorization automatically. Account deletion does not cancel a subscription; cancel it with the provider that bills you.

Contact

For privacy questions, use the WrenSlicer support page.