if you want to see a .gpx online , you can try this :

http://www.zonums.com/gmaps/gpxviewer.html

See sample of a gpx trip :
Click image for larger version. 

Name:	2011-05-29 16h49_15.jpg 
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but with ATOM GPS you have more option like the timeline to know where you were , when and the direction of the trip.

if anyone knows better gpx viewer online, I would be happy to check them and add to the thread

gpx is a popular format generated by gps data logger device , it's also the most common format for photo geo tagging.

you can also produce a gpx track file with gps stone for iphone