# Letterproof — WCAG contrast & font audits > WCAG contrast & font audits (iPhone/iPad app by Robert Corbin.) - Source: https://appshunter.io/ios/app/letterproof/id6776838156 (this page in markdown: same URL + `.md`) - Developer: [Robert Corbin](https://appshunter.io/developer/1890247992) - Category: Graphics & Design, Utilities - Price: $2.99 - Age rating: 4+ - Requires: iOS 17.0 · 4 MB - Languages: American English - Released: 2026-06-09 - Data updated: 2026-08-19 - User reviews in markdown: https://appshunter.io/ios/app/letterproof/id6776838156/reviews.md ## What is Letterproof? Letterproof grades the type around you. Point the camera at a menu, sign, slide deck, print proof, worksheet, UI mockup, or screen. Letterproof finds each visible line of text and rates it against WCAG 2.2 accessibility contrast thresholds. Each reading shows: - AAA, AA, or FAIL verdict - Exact contrast ratio, such as 4.51:1 - Sampled text and background colors - Estimated text size - A color-coded overlay on the source image - A practical contrast fix when a region falls below AA Letterproof is useful for designers checking a proof, teachers or parents reviewing low-vision readability, content teams reviewing signage or brochures, and anyone curious whether text in the real world is actually readable. Built privacy-first: - Vision text recognition runs on your iPhone or iPad - WCAG math runs on your iPhone or iPad - Photos and camera frames are not uploaded by the app - No account, sign-in, ads, tracking, analytics, or subscription - Audit history is saved locally on your device WCAG thresholds checked: - AA: 4.5:1 for normal text, 3:1 for large text - AAA: 7:1 for normal text, 4.5:1 for large text - Large text is treated as approximately 18 pt or larger Settings let you review results against an AA or AAA target. One-time purchase, no subscription. ## Version history (last 5 releases) ### 1.4.1 — 2026-06-26 This update sharpens the interface: the iPad layout now uses a centered, comfortable reading width instead of stretching edge to edge, plus small display fixes. iPhone is unchanged. ### 1.4 — 2026-06-23 What's New in Letterproof 1.4 Palette Contrast Matrix - the new Palette tab lets you enter your entire design-system colour palette (up to 12 colours) and see an NN compliance grid in one view. Every text/background combination is scored simultaneously: each cell shows the WCAG grade (AAA/AA/FAIL) and the contrast ratio right on the coloured background, so failing pairs are visible at a glance. Toggle to large-text thresholds with one tap. Tap any cell for a full detail sheet: contrast bar, APCA Lc score, colour-fix suggestions, and colour-blindness simulations. Share the full matrix as a plain-text report. The palette is saved between sessions. Bold-text threshold - WCAG 1.4.3 defines large text as 18 pt regular *or* 14 pt bold, but Letterproof previously applied only the 18 pt boundary (the conservative fallback when weight isn't detectable from pixels). A new `isLargeTextSize(_:isBold:)` API now supports both boundaries. The Manual tab's large-text toggle label clarifies the 18 pt regular / 14 pt bold distinction, and the ReadingDetailSheet explanation text references the bold rule. ### 1.3 — 2026-06-18 Export a shareable Accessibility Report — a polished PDF (and annotated PNG) of any audit, ready to drop into a compliance ticket, parent-teacher packet, or client deliverable. Plus contrast-accuracy and overlay-alignment fixes for portrait camera photos and wide-gamut images. ### 1.2 — 2026-06-15 What's New in Letterproof 1.2 Colour-fix suggestions — when any text region fails WCAG AA, Letterproof now shows up to four alternative colours that would pass: darken text, lighten text, darken background, or lighten background. Each suggestion keeps the original hue and saturation, changes only lightness, and shows the contrast it achieves. Tap any hex code to copy it to the clipboard. Available in both the reading detail sheet and the Manual tab. APCA Lc score — every contrast check now includes the APCA (Advanced Perceptual Contrast Algorithm) perceptual-contrast score alongside the WCAG 2.2 ratio. APCA is the contrast method being evaluated for WCAG 3; it is polarity-aware and better reflects how human vision perceives lightness differences. A readability note (body text / UI text / headlines / too low) appears next to the Lc value. Clearly labelled as experimental — WCAG 2.2 remains the enforceable standard. CSV export — the share menu in any audit result now offers "Export CSV" in addition to the existing plain-text report. The CSV file has 11 columns — WCAG grade, contrast ratio, APCA Lc, OCR text, estimated point size, foreground hex, background hex, and audit timestamp — sorted worst-first. Open in Numbers or Excel, or paste into an accessibility report template. ### 1.1 — 2026-06-14 What's New in Letterproof 1.1 Manual colour checker — a new tab lets you type any two hex colour codes and get an instant WCAG contrast ratio and AA / AAA verdict. Flip a toggle for large-text thresholds. No camera needed — useful any time you are reviewing a Figma file, design brief, or brand guide. Colour-blindness simulations — every reading detail sheet now shows how the text / background pair appears under Deuteranomaly, Protanomaly, and Tritanomaly. The simulation uses the Machado et al. (2009) physiologically-based model. The Manual tab includes the same simulations for any colour pair you type in. A red-on-green pair that passes WCAG on paper might still fail readers with colour-vision deficiency — this makes that visible. Share / export — tap the share button from any audit result to get a plain-text report with the overall verdict, region count, and every reading's grade and contrast ratio. Also available in the Manual tab. ## More apps by Robert Corbin - [Daily Word Journey](https://appshunter.io/ios/app/daily-word-journey/id6761548266) - [Hush Secret Text](https://appshunter.io/ios/app/hush-secret-text/id6761658175) - [Renew Guard](https://appshunter.io/ios/app/renew-guard/id6761755447) - [Receipt to PDF](https://appshunter.io/ios/app/receipt-to-pdf/id6761782025) - [Route Your Pay](https://appshunter.io/ios/app/route-your-pay/id6761783719) - [Tip Arbiter](https://appshunter.io/ios/app/tip-arbiter/id6761786879) All apps by Robert Corbin: https://appshunter.io/developer/1890247992 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-19.*