Foldbook
PRIVACY POLICY
Your desktop stays on your Mac.
LAST UPDATED 14 SEPTEMBER 2026 · APPLIES TO DUODISPLAY 1.0.0 AND LATER, INCLUDING THE MAC APP STORE BUILD
Who this policy covers
This policy describes the Foldbook app for macOS, published by Shivam Chopra, in both of its builds: the version distributed on the Mac App Store and the direct-download version published on GitHub. The two builds are compiled from the same source code and behave identically, except for the update mechanism described below.
What Foldbook does with your screen
Foldbook animates your desktop as the MacBook lid moves. To draw that animation it needs a live copy of what is on the built-in display, which it obtains through Apple's ScreenCaptureKit after you grant Screen Recording permission.
- Screen frames are captured only while the effect is running, that is, while the lid is moving and the animation is on screen. Capture stops as soon as the desktop clears, when you pause the app and when you quit it.
- Frames stay in memory on the graphics processor and in a small, bounded buffer. They are never written to disk, never saved as images or video, never analyzed, and never sent anywhere.
- Audio is never captured. Foldbook's own windows are excluded from the capture.
- Screen Recording permission is used solely to render the effect. Nothing else in the app reads the screen. You can revoke the permission at any time in System Settings → Privacy & Security → Screen & System Audio Recording; the app then falls back to its built-in preview artwork.
The lid-angle sensor
Foldbook reads the angle of the lid from the sensor built into recent MacBooks. The reading is a single number that drives the animation. It is not logged, stored or transmitted. On a Mac without the sensor the app still runs and shows the effect with the Replay and Test desktop buttons.
Network access
| Build | Network activity |
|---|---|
| Mac App Store | None. The App Store build contains no networking code. It never connects to any server, and updates arrive through the App Store itself. |
| Direct download (GitHub) | The app contacts GitHub only when you choose Check for Updates, to read the latest release information and, if you confirm, download the new version over HTTPS. There is no background polling. The request carries no identifier, no preference and no screen content; GitHub sees the same connection information any web request carries and handles it under GitHub's privacy statement. |
Preferences
Your settings, such as the chosen effect, its tuning, the appearance, whether the menu-bar icon is shown and whether the app opens at login, are stored locally on your Mac in the app's standard preferences. They never leave the device. Removing the app or resetting to defaults removes or restores them.
Permissions the app may ask for
| Permission | Why | Required? |
|---|---|---|
| Screen Recording | To render a live copy of the desktop inside the effect. | Only to animate your real desktop. The preview and Replay work without it. |
| Open at login | To start the app when you log in, if you turn that option on. It opens paused. | No. Off by default. |
The Mac App Store build runs inside the macOS App Sandbox. Its only additional entitlement lets it read the built-in lid-angle sensor; it has no entitlement for the network, your files, your camera, your microphone, your location or your contacts.
What Foldbook does not do
- It does not collect personal information of any kind.
- It does not use analytics, telemetry, crash reporting or advertising.
- It does not require or offer an account.
- It does not include third-party SDKs or frameworks; it is written in Swift and Metal using Apple's system frameworks only.
- It does not track you across apps or websites, and it does not share data with anyone, because it has none to share.
Children
Foldbook is suitable for all ages and does not knowingly collect information from anyone, including children, because it collects no information at all.
Open source
The complete source code is published under the MIT License at github.com/shivamchopra7/Macbook-Duo-App, so every statement on this page can be checked against the code.
Changes to this policy
If the app's behaviour ever changes in a way that affects privacy, this page will be updated and the date at the top revised. The policy is versioned with the source code, so its history is visible in the repository.
This website
Everything above describes the app. This website, macbookduo.illusionart.ai, is separate: it uses Google Tag Manager to run measurement tags such as Google Analytics, so the publisher can see how many people visit, which pages they read and where they came from. These tags may set cookies and receive your IP address, browser and device details and the pages you view, which Google processes under the Google Privacy Policy. Nothing from the app is ever sent to them. You can block them with a content blocker or opt out of Google Analytics with Google's opt-out browser add-on.
Contact
Questions or concerns about privacy are welcome on the project's GitHub issues page: github.com/shivamchopra7/Macbook-Duo-App/issues.