What’s wrong with using a GPS smart-phone with a proper navigation app?

Aside from the competition rule above, anyone with any real experience of smart phones in mountain conditions will know that they are not to be relied upon – especially in cold or wet conditions. Phone batteries are particularly prone to suddenly dying when cold and, of course, if you drop your phone in a bog hole it’s knackered. A phone is great for use in emergencies and should be kept safely wrapped in a plastic bag in your rucksack or an inside pocket.