Simon Wheatcroft has been blind since the age of 17 but has refused to let his lack of sight prevent him taking part in his great passion for running.

He has run marathons around the world and even attempted a 150 mile ultra-marathon across the desert in Namibia.

The desert run was to prove a particular challenge and a smartphone app was developed for Simon by IBM Blumix Garage to help keep him on course.

The app was a key component allowing Simon to compete alone. He managed almost 100 miles into the race before having to pull out because of the terrain and extreme heat.

BBC Disability Index.

BBC Click's Spencer Kelly spoke to Simon about his experiences of running without sight.

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