Most of my clients use Livestrong or MyFitnessPal , I do believe they all work as long as you are truthful about what you eat, how much you eat, and how much you do or don’t workout or exercise. I believe it makes the person more conscious of what they are eating and how many calories they are burning. All comes down to accountability.
I get the majority of my clients to use LoseIt. Its a great free app that you can download to iPhone or android. It has the ability to scan barcodes, and has a large database to draw from. You can also log in online and track through your computer. www.loseit.com
Database of 7,000+ food items with 46 Nutrients.
Search database of food in the meal or select a meal previously eaten by meal name.