I do not (yet) own an iPhone or iTouch. But these kind of applications are tempting me.
Simple GPS interface software.
Download Trailguru and capture your outdoor activities using the iPhone 3G’s integrated GPS.
Both these two iPhone applications are now free.
Jason Jacobs of Fitness Keeper, the developers of RunKeeper, announced yesterday that the company is going to make the application available for free …
There are other options including The Running GyPSy and iTrail. All offer more than the basic Nike + iPod Sport Kit.
related article: TUAW Faceoff: Nike + iPod versus iPhone 3G Challengers
besthike.com 
I’ve tried all of the applications mentioned above but have fallen in love with Fitnio.
It is the best free Fitness app out there for the iphone. I love that it even tells me how many calories i’ve burned during my run!
Check it out:
http://www.fitnio.com
Just downloaded Fitnio and the other two. Will check out all three.
THANKS Beth.