When it comes to losing weight, there is no silver bullet. Eat less, exercise more.
iCountCalories started as a project for myself when I was losing weight (55lbs and dropping!) It is a simple, intuitive app that lets you set a goal for how many calories you want to eat each day, lets you track what you have eaten, and shows you historic charts about your progress and your eating habits. iCountCalories also has a database of commons foods and their calories so that you dont have to do all of the hard of determining how many calories are in what you just ate.
Give it a try, let me know what you think