Mount Everest 3D is a free universal iOS app that brings you up close to the highest mountain in the world using 3D data gathered from satellites to give you the ability to explore the mountain with a touch interface. You can zoom, rotate and follow the most popular routes up to the summit of Mount Everest. The app also shows weather in the area, details for hardy tourists and a 2D view.
The app also has the inevitable in-app purchase, which lets you download maps and info for use without an internet connection, but I think most people can get along without it. The on-board maps are US$5.99.
Using the app was educational, and i enjoyed exploring some of the routes up to the top of Mount Everest. A few things were a bit flaky. Webcam images did not appear, but I'm not sure how reliable those cameras are up there. Same for local weather on the mountain, which provided me with an error message. Still, everything else worked well, and the app certainly makes you want to visit. Even better, your iPhone might work while you're visiting Mount Everest, as we reported a couple of years ago that there is 3G service on the mountain.