Health/fitness phone apps: which ones do you use?

Curious to know which phone apps you enjoy using for tracking meal and fitness plans.  So many out there that I'm not sure which one I'd like to use now that I have an iPhone.  I downloaded DailyBurn Tracker but the darn thing wouldn't stop crashing or even accepting a password so I removed it.  OH doesn't seem to have a phone app.  I don't believe SparkPeople does either.  Tempted to try FitDay's app but wanted to get feedback if that one is great or something else is easy to use and informative.

thanks