This iPhone app has a great feature set for calorie, exercise and weight tracking, although it is not without its problems. Overall, it needs a little "spit and polish." The foods I logged often failed to save correctly when I initially entered them. Instead, I'd have to save them, then go back and edit them in order to adjust time of day, or servings eaten. It wasn't a huge deal, but calorie tracking should be quick and easy to encourage me to keep doing it. If every entry takes twice as long because of editing, well, I'm probably going to give up eventually. Which I did.
In addition, the exercise trackers seem very skewed. LIVESTRONG tells me that a 2-hour bike ride burns about 1,600 calories, while Trailguru gives a much more conservative 750 for the same time and distance. When trying to lose weight, you should overestimate calorie input and underestimate calorie burning in my opinion. I learned pretty quickly to ignore however many calories it said I was burning.