A Scottish rescue leader says anyone venturing into the mountains should rely on the old-fashioned map and compass, not high tech apps and GPS. Simon Steer, deputy leader of the rescue team in the Cairngorms, made his comments after two groups with a total of 16 people had to be rescued in the Highland mountain range Monday, The Guardian reported. Both groups had depended on smartphone apps as route guides. \"It\'s great that more people are venturing into the hills, but we need to be very aware of the limitations of new technologies and avoid relying solely on them,\" Steer said Tuesday. \"Apps don\'t give you a risk-free passport to the mountains -- if nothing else, the batteries don\'t last indefinitely.\" Steer said both groups also did not carry the kind of clothing and other equipment needed for the weather high in the Scottish mountains. He said anyone going into the hills needs to carry a map and compass and to know how to use them. One party of 14 people became confused by fog on Ben Macdui, the second-highest mountain in Britain. They were taken off the mountain early Tuesday with the rescue effort involving police, mountain rescue teams and a Royal Navy search and rescue helicopter, The Guardian reported.