Skip to content
BesstaCalister

Calister

Privacy Policy

Effective Date: October 2026

Overview

Calister is a Mac app for drawing precise 2D shapes and painting them. Everything it does happens on your Mac. It has no account, no cloud service and no server, and it cannot connect to the internet at all: the app is sandboxed by macOS without network access.

The App does not collect, use, store, or share any personal information.

Information Collection

The App does not collect any data of any kind.

Specifically, the App does not collect:

  • Personal information (such as name, email address, or contact details)
  • Device information or identifiers
  • Usage data or analytics
  • Location data
  • The contents of your drawings

Your Documents

Your drawings are files you save yourself, wherever you choose to save them, in an open format (.calister, which is readable JSON). Calister can only read and write the files you pick in an Open or Save dialog, or drop onto its window; macOS does not let it see anything else on your Mac.

If you save a drawing in iCloud Drive, it is stored and synced by Apple under your own iCloud account, as with any other file there. Calister never receives a copy.

Exports (SVG, PDF, PNG and DXF) and printing go only where you send them.

Finder Previews

Calister includes two small extensions that let the Finder and Quick Look show a picture of a .calister file. They draw the preview on your Mac, from the one file macOS hands them, and send nothing anywhere.

Settings

Your preferences, such as the size of your panels or the page size you last chose, are kept on your Mac in the App's own settings. They never leave it.

AI Tools (Off by Default)

Calister has an optional setting, Settings ▸ AI tools ▸ Allow AI tools to drive Calister, which is off unless you turn it on.

When you turn it on, an AI assistant you have set up yourself on your Mac (such as Claude Code, through a small connector program you install) can read the open drawing and make changes to it. The connection stays on your Mac and is protected by a private key that Calister keeps inside its own storage.

What the assistant does with your drawing afterwards is governed by that assistant's own privacy policy, not this one: many assistants send what they read to their provider's servers. Calister sends nothing to anyone itself, and with the setting off it answers no outside program at all.

Crash Reports and Beta Feedback

Calister contains no crash reporting or analytics code of its own.

If you test Calister through Apple's TestFlight, Apple shares crash reports with the developer, together with any feedback, screenshots and comments you choose to send through TestFlight. If you install Calister from the App Store, Apple shares crash reports and usage statistics with the developer only if you have agreed to share them with app developers in your Mac's settings (System Settings ▸ Privacy & Security ▸ Analytics & Improvements). These reports are handled by Apple under Apple's privacy policy, and they do not identify you to the developer.

Third-Party Services

The App does not use any third-party services, including:

  • Analytics providers
  • Advertising networks
  • Crash reporting tools of its own
  • External APIs or cloud storage

Data Sharing

No data is collected by the App; therefore, no data is shared with Bessta or any third party.

Children's Privacy

The App does not knowingly collect personal information from anyone, including children.

Security

Because the App cannot connect to the internet and sends nothing anywhere, there is no risk of personal data exposure through the App itself. Your drawings remain under your control, in the files you saved.

International Use

The App is available worldwide. No personal data is collected or transferred across borders.

Changes to This Privacy Policy

This Privacy Policy may be updated from time to time. Any changes will be reflected by updating the Effective Date above.

Contact

Questions about this policy: [email protected]. For any required legal or regulatory contact information (including under applicable laws such as the Digital Services Act), please refer to the App Store listing or developer information provided with the App.

Summary

  • No data collected
  • No tracking
  • No internet access
  • Your drawings stay in the files you save
  • The AI tools setting is off unless you turn it on