Designing a more accessible tube map
The iconic London underground map is relied on by millions of travellers every day, but its white background, small text and low contrast differences in colour can cause problems for people with many different types of impaired vision. We (232 Studios and Ian Hamilton) have recently launched an award winning app to overcome this.
We first became aware of the problem through an article on accessibility on smartphones in the Guardian, where a colourblind Londoner was bemoaning the fact that tube map smartphone apps are not accessible to him. There is a black and white pattern-based map available, but only as a PDF, not in the same medium that everyone else is able to use at their convenience. So we set out to remedy this, and bring a more accessible map to smartphones.
The existing black and white map is actually left over from the time before colour printing became cheaply available, it isn’t actually designed for colour-blindness, so the first enhancement was to produce something that was actually tailored to that audience, that combined colour with pattern to create something ideally suited to people who see in a restricted palette.
Additionally, due to our past experience working on video magnifier software, another use soon became apparent. A pattern based map is free from being constrained by colour choice, meaning those colours can be altered to suit the preferences of people with a wide range of different vision impairments. So we used some principles from the video magnifier industry, namely different proven colour combinations (colour on white, colour on black, white on black, black on white, yellow on black, yellow on blue) combined with a very high level of zoom, to go beyond colourblindness and allow additional modes for other types of vision impairment.
Lastly, when developing assistive technology it is critically important to remember that you are not developing software or hardware for an impairment. You are developing software or hardware for people who have an impairment. So as impaired vision is so strongly tied to age and more likely to go hand in hand with other minor-moderate impairments, it was essential for us to take into account as many other accessibility considerations as possible. These include larger than usual buttons, choice of font size, simple clear literal iconography, and easy tap controls rather than complex pinch/zoom.
We had planned the app for a long time, and what finally gave us the push to get it finished up and released was Transport for London’s contest to design apps that might help Londoners and visitors navigate London more easily. We were lucky enough to win the judges’ award, which carried some prize money, so after that we were able to write off the prize money against the development costs and make the app free.
The approach that we have taken with this app is an example of the benefits that digital technology has been able to bring to people with all kinds of impairments. The tube map in the station is a single physical object that has to compromise to work for as many people as possible, but digital products are not bound by the same constraints. Interfaces can be customised, the best possible solution tailored to each individual’s need.
Having said that, there are some simple basic principles that are applicable to all map design, and encouragingly we’ve had quite a bit of interest from the cartography community. Using symbol/pattern as well as colour, or providing high detail imagery that can in turn support a high level of zoom; these are things that are applicable to all maps.
So it’s our hope that the principles in the app might be taken up by other designers for other projects and in other countries, spreading the word about universal design, and continuing to remove the unnecessary barriers that make it more difficult for people to live their lives as comfortably, as independently, and as equally as possible.
This article was taken from the DeafBlind UK website, you can view the original article here.