<human>:  What is the best fitness app to track calories?
<bot>: The best fitness app to track calories is MyFitnessPal. It is a free app that allows you to easily log meals, track calories and create personalized diet plans to help you reach your health and fitness goals. It also has a large food database with millions of foods and recipes to choose from, making it easy to get nutrition information quickly. Additionally, MyFitnessPal offers tracking options for macro and micronutrients as well as detailed analytics, making it one of the most comprehensive calorie tracking apps available.