One of my colleagues t work showed me a new app that he has for his iPhone called Peak Scanner. The app interrogates a file which contains over a million image details of 250,000 mountain peaks across the world, probably stored on a cloud; this could be checked by turning the mobile data off on the phone. By pointing your iPhone’s camera at a specific peak which the app then tries to recognise. Evidently it does this by narrowing down the number of files it needs to interrogate by identifying your location using the phones in-built satnav.
http://www.quantaq.com/peakscanner/