This app seems really popular... Surely it works!! Already I've noticed the difference by using this app guys...
It keeps me in check
Who else loves it mmmm?
I use it.
Mainly to check protein intake of the day. And to make sure I don't go overboard on kcals. Works like a charm. Also to track weight progress by filling in my weight once a week.
I use MFP and it works wonderfully. But it, like all other fitness related apps, represents extrinsic motivation. While I feel that it is a great tool and will help you track food and macros, it won't motivate you unless you are motivated already. My knowledge on the subject is the result of years of personal experience. If you're motivated to track what you eat and really refine that part of your lifestyle, MFP is a fantastic resource.