Every day, write down everything you eat, and take a quick review of your day each night.
It is composed of 5 parts:
    Breakfast
    Morning snack
    Lunch
    Afternoon snack
    Having dinner
You can find the history of all your registration for 1 year and you can even plan your meals for the next 4 weeks.
No need for internet connection, no advertising, everything is saved on your phone.