I searched for this app and nothing came back on this forum. Maybe this app is new news. Thought the developer would have posted about it here already, I probably missed it somehow. It uses phone GPS and downloaded maps combined with Google Maps Interface. Looks like it might be a cool tool for the mountaineers route, but the main trail is so obvious. They're working on a full JMT version which would seem to be more useful.
Mt Whitney Guide Smartphone App 
