Letterproof Privacy Policy
Effective date: June 13, 2026. This policy explains how Letterproof handles data.
Data Handling
Letterproof is designed as a fully on-device app. Audit history, settings, and the WCAG target preference are stored locally on the device using a JSON file (Documents folder) and UserDefaults. No data is sent to any server by the app itself.
Camera and Photos
When you use the Audit tab, Letterproof requests access to the camera or photo library to capture or load an image. The image is processed on-device by Apple Vision OCR and Letterproof's colour-sampling code. No image or OCR result is uploaded, transmitted, or stored outside your device. Images are not retained after the audit completes — only the numeric audit record (contrast ratios, bounding boxes, grades) is saved.
Manual Tab
The Manual tab accepts hex colour codes you type. No image, photo, or camera access is used. The calculation is performed locally. Nothing is transmitted.
Colour-Blindness Simulations
Simulations are computed locally using a mathematical matrix applied to the sampled RGB values. No additional data is collected or transmitted.
Share / Export
Tapping "Share report" generates a plain-text string locally and presents the system share sheet. Data only leaves the device if you explicitly choose to send or save it through the share sheet. Letterproof does not control where you send that data.
Tracking and Third Parties
Letterproof does not track users across apps or websites. It does not include any third-party analytics, advertising, or tracking SDKs. There is no account system and no sign-in.
Permissions
Letterproof requests camera access (for the Audit tab camera option) and photo library access (for the Audit tab photo import option). The Manual tab requires no permissions. No other sensitive system resource is accessed.
Children
Letterproof does not knowingly collect personal information from children. The app has no account system and no network data collection.
Contact
Questions can be sent to RobertCorbin84@gmail.com.