Cyclemeter for iOS. Still looking for the ideal iPhone mount however. I usually just start the app and toss the phone in my jersey pocket and forget about it. It now has a function where it analyzes for and compensates for time spent stopped. I find it usually tracks my Bike Computer on ride time within about 15-20 seconds.

I also use LoseIt to track my calorie intake and exercise. I often credit this app with helping me lose 40 pounds - and keeping it off now for over a year.