DICHROMACY

iPhone Safari build — test the color model locally, then apply the same controls directly to ordinary webpages.

1. Verify the simulation

Open the built-in reference page first. It runs on this same site, so Safari's cross-origin iframe restrictions are removed from the test.

OPEN COLOR TEST

2. Install the Safari filter bookmark

The bookmarklet injects a small control panel directly into whatever normal webpage you're viewing.

  1. In Safari, bookmark this page.
  2. Edit that bookmark and rename it Dichromacy Filter.
  3. Replace the bookmark's URL with the code below.
  4. Visit a normal webpage, open Bookmarks, then tap Dichromacy Filter.

3. Open a page

Enter a website here. It opens normally in Safari; then invoke the Dichromacy Filter bookmark.