...get this app ASAP!! My Fitness Pal. My friend, Elizabeth, introduced me to this app the other day and I think it is amazing! You bascially enter in your personal info, amount of weight you would like to lose, gain or maintain, and it will calculate for you the amount of calories you need to consume a day. Essentially, it is an electronic food and exercise diary. You enter in all of your food intake--which I LOVE because it has most mainstream restaurant dishes and their calories and also foods you eat at home. So cool. You also can gage your exercise caloric burn. You can also keep a diary at home on-line. Just love it. And get this: It's FREE. Check it out ta-day.