1) LIVESTRONG Calorie Tracker (US$2.99). Probably the best all-around fitness app on the App Store, this universal (runs on iPhone and iPad) app is a way to help you achieve your weight and fitness goals without joining a weight loss program. All you need to do is go to Livestrong.com, a site inspired by Lance Armstrong's Livestrong Foundation, and sign up. Through the app, you can then compare the calories you ingest to your daily goal, see a day by day chart of your weight, search for caloric values for different foods (both raw, packaged, and available at restaurants), and track the number of calories burned in daily exercise. For walkers, runners, and bikers, there's a way to track the distance you've gone and your heart rate. It's an excellent app for those who want to reach a goal without signing up for an expensive weight loss program.
2) Weightbot ($1.99). While this iPhone app from Tapbots is a bit of a single-tasker, it does that task very well. All Weightbot is designed to do is to track your weight and view your body mass index (BMI). Like all Tapbots apps, Weightbot is beautifully designed. If you happen to own a Withings Connected Scale, you don't even need to hand-enter your weight -- your scale will send that reading to the app automatically through the Withings website.
3) Weight Watchers Mobile (free). Designed to work with the Weight Watchers Online program (subscription required), Weight Watchers Mobile is a very complete iPhone application that does a lot. Weight Watchers allows dieters to eat anything, but requires that you track the number of "points" you eat every day. The app has a built-in PointsPlus Tracker for adding meals and snacks to the list, allows you to subtract points for exercising, has a weight tracker for seeing where your weight is on a weekly weigh-in, a PointsPlus Calculator for determining the number of points from nutritional information on packaged foods, and a daily "healthy check" to make sure you're drinking enough water, eating enough fruit, taking a vitamin supplement, and more. There are recipes, articles that are targeted to you (I'm on the Weight Watchers Men's Online plan, so I see hints that are specific to males), motivational success stories, and more.
4) Weight Watchers Kitchen Companion (free). An excellent resource for anyone who wants to learn to "eat right," the Weight Watchers Kitchen Companion iPad app is helpful even if you're not a Weight Watchers member. For free, you get featured recipes, can create custom shopping lists, and have the ability to tap cooking times in recipes to automatically start a kitchen timer. Recipes can be shared over email or with Facebook friends. Weight Watchers Online members get access to many more recipes, special ingredient, shopping, and equipment guides, a Recipe Builder for creating your own recipes, and the ability to send recipes to the Plan Manager (part of the Weight Watchers Mobile app) for tracking points.
5) RunKeeper Pro ($9.99, free Lite version available). I've tried just about every app out there for tracking my walks, hikes, and bike rides, and I've settled on RunKeeper. The app eliminates the need for a standalone fitness tracking device, calculating the distance you've gone, recording the time it took, and creating a track of your route. Both the Pro and Lite versions store your exercise info on the RunKeeper.com website, and it's fun to connect RunKeeper to your Twitter and Facebook accounts for motivational pressure from friends and relatives. Like the Weightbot app discussed above, RunKeeper can be linked to your Withings Scale for automatic tracking of your weight.
6) Fitness HD for iPad ($2.99). Want to bring strengthening or flexibility exercises into your routine? Would you like to have a personal trainer or Yoga instructor, but you can't afford one? Fitness HD has an internal database of over 700 exercises for men and women, along with video instructions for every exercise. There are also 50 Yoga poses in the database, with video and audio instructions. That's not enough? They also have 40 ready-made workouts built in, developed by professional fitness trainers. The app can also let you track calories consumed and burned if you're not already using another app to do that.
Those are my choices for six solid apps for tracking weight and calories or keeping up with your exercise routine (if you have one). Do you have a favorite exercise or dieting app that you can't live without? Share your success story with us in the comments below.