🔒 LetCube — Privacy Policy
Effective: July 12, 2026 · Last updated: August 6, 2026
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Contact: [email protected]
LetCube collects no personal data. There are no servers operated by us, no analytics, no tracking, no advertising, and no account or login — and the app runs fully offline. This App is fully compliant with Apple's "Made for Kids" guidelines and the Children's Online Privacy Protection Act (COPPA). We do not collect any personally identifiable information from users, including children under the age of 13.
The camera, in plain words
LetCube's scanning mode uses the camera for one purpose only: to read the colors of the squares on the physical cube you are holding, in real time, entirely on your device.
- Camera frames are held in memory only and are discarded immediately after the colors are read.
- They are never saved to disk, never added to your photo library, never recorded, and never uploaded — the app makes no network connections at all.
- No faces, people, or surroundings are detected, identified, or stored. The app looks at color patches only.
- If camera permission is declined, or the device has no camera, the child can enter the cube colors by hand and still use every part of the app.
What the app stores, and where
- Settings (cube color pack, spoken guidance on/off, sound effects on/off, animation speed) are stored on your device only.
- Progress (Cube Academy lessons completed, best challenge level, practice points, and best stars per round) is stored on your device only and never transmitted to any server.
- Nothing is linked to an identity: there is no account, no profile you register, and no identifier of any kind.
What we do NOT collect
- No name, email address, age, photo, or any personal identifier — the app never asks for them
- No location data
- No voice or audio (the app requests no microphone permission and performs no speech recognition; spoken guidance is generated on-device by the system speech synthesizer)
- No camera images (see above — analyzed in memory, then discarded)
- No usage analytics or crash reporting sent to us
- No advertising identifiers (IDFA); we do not use App Tracking Transparency (ATT)
- No third-party SDKs that collect data
Apple's App Privacy label
In App Store Connect, LetCube is declared as Data Not Collected, and Tracking is set to No. That declaration matches exactly what this page describes: no data of any kind is gathered, and the app never tracks users across other apps or websites.
Children's privacy (COPPA / GDPR-K)
LetCube is designed for children to use under parental supervision. Because we collect no data at all, the app complies with COPPA (US) and GDPR-K (EU) by design. No information about child users is ever collected, stored outside the device, or shared.
Permissions
LetCube requests only one permission, and only when you first open the scanning mode: camera. It does not request microphone, photo library, location, contacts, notifications, or Bluetooth access. Camera access is optional — the app remains fully usable without it.
Third-party services
LetCube uses no third-party analytics, advertising, or tracking services, and makes no network connections.
Third-party asset licensing
The cube-solving engine is based on the open-source Min2Phase solver by Chen Shuang, used under the MIT license. It is a pure algorithm that runs on-device and collects no data. All sound effects are original LetCube tones released under CC0 1.0. These components involve no data collection of any kind.
Ad-Free Experience
To ensure a safe environment for children, this App is 100% ad-free. We do not display any third-party advertisements or use any ad-tracking mechanisms.
Outbound Links & Parental Gate
Any external link (such as a support email, an App Store page, or any purchase entry point added in the future) sits behind a Parental Gate — a multiplication question that children cannot pass by guessing. The entire Settings screen is behind this gate, so children cannot reach the internet or leave the App without adult supervision.
Our other apps
Behind the parental gate, Settings shows a shelf of our own child-friendly apps. If one is already installed, the shelf opens it directly; if it is not, the shelf shows its App Store page using Apple's own in-app product sheet. This shelf lists only apps made by us — there is no third-party advertising, cross-promotion network, tracking, or external web content.
Purchases
The initial release is completely free with no in-app purchases. If an optional donation or paid feature is added later, its entry point will always sit behind the parental gate and be handled by Apple's payment system; we never see or receive your payment details, and this policy will be updated accordingly.
Data deletion
All app data is stored locally on your device. To delete it, simply uninstall the app — everything it stored goes with it.
Changes to this policy
If this policy changes, we will update the effective date above. Significant changes will be noted in the App Store release notes.
Contact
Questions? Email [email protected].