Harry Beck's topological Tube Map is an instantly recognisable design icon, even for those who have never navigated the London Underground. Sure, the clean geometry makes it easy to figure out the best route, but it's the variety of Pantone hues assigned to each line that gives it true at-a-glance readability. That is, if you're not colourblind.
Last month, Transport for London announced the winners of its accessible app competition, and the judges selected this smart update by 232 Studios and Ian Hamilton, designed for folks who can't see the spectrum, as the winner.
Here, each of the lines is assigned a distinct pattern that differentiates it without the need for a specific hue. The app itself has a straightforward layout that befits the source material — basically, it's a zoomable map, viewable in six interfaces to accommodate a variety of vision impairments.