I tried this out using an airplane flight path generated on my iPad using the Foreflight app. From Foreflight I “Viewed on Foreflight.com” in Safari. From there I clicked on the GPX button and saved it to Dropbox, which (also) put it on my home computer. From my Mac, I opened the flight path in gpx viewer and it displayed immediately. After 5 minutes of tinkering to learn the app, I finally figured out how to display the entire route in 3D with a tabular listing of the altitudes. That was nice. Even nicer, I clicked on Satellite tab and zoomed in to the airport and was rewarded with a close-up showing how well the airplane took off and landed along the center line of the runway, as well as how straight and centered the airplane was during taxi. I gave it 5 stars for ease of use right out of the box and because of the value for the 99c price, though it lacks one feature that I have seen in other gpx viewers. Namely, it does not import the route time (maybe this is a weakness of Foreflight — not sure) for each waypoint and thus there is no “RUN” button to click to watch the airplane traverse the flight path. Also, the buyer should be aware that this is sort of the “lite” version of the app. There is another “version” called the gpx editor that has more features and costs more.