It’s easy to imagine that being blind or visually impaired more or less excludes people from using smartphones or tablets. But nothing could be further from the truth. App stores have a dizzying variety of products that help the visually impaired access all kinds of information much more easily than would otherwise be possible. These apps offer audio books, match clothes by colour and even offer games played by hearing and touch alone. But the apps designed to give directions all suffer from the same drawbacks—audio directions are helpful but also screen out other audio such as conversations or the sound of traffic nearby. What’s more, GPS does not work indoors so these kinds of systems are of little use in homes and other buildings. Now Pierluigi Gallo and buddies at the University of Palermo in Italy have come up with an alternative which offers the blind navigational help without any form of audio distraction or the need for GPS. The approach is surprisingly simple and inspired by the famous Greek myth of Ariadne and Theseus. Read the full story at Technology Review.