MyFitnessPal is a very useful app for losing weight by counting your calories, making sure you eat healthy and exercising. Read more about MyFitnessPal  

You can count the calories in foods you’ve eaten during the current day and check a large database with various foods and recipes that you can check out. The app connects with multiple devices and apps, including Jawbone, Strava, Runtastic, Runkeeper, Withings, Misfit and many more.
MyFitnessPal helps you import recipes from the web, create your own custom foods and exercises so you can lose weight and reach your goal. Moreover, it helps you get nutritional reports, calculate nutrients for various foods, scan barcodes and check out multiple exercises for losing weight. It also comes with tools for tracking all major nutrients in foods, including fat, proteins, sugar, carbs, fibers and many more.