I lost 30 lbs with the app, MyFitnessPal, after having my 2nd baby.
I just started using it again recently to continue my progress.
I have tried many different food and exercise diaries but this app is by far my favorite!
Logging my plan for the entire day in advance works best for me versus logging it as I go. I tend to lie to the app (and myself) if I log throughout the day. Whatever works!