I'm a fan of Cyclemeter. It's a great program for tracking your rides, and runs in the background on iOS4 devices. It also uses GPS for tracking and seems to be quite accurate, except for the total amount climbed, which seems to be inconsistent. You can easily export the info to different formats to share, including Google maps, GPX, KML, and CSV files. It also doen't use much battery when running, even though it's accessing the GPS all the time. On a 2hr ride, the program uses about 10% battery on my iP4.

Here's an example of the map link from the program:
http://maps.google.com/?q=http://sha...01120-0643.kml