The mHealth Summit, held in early December near Washington, D.C., showcased several smartphone applications designed to track your behaviors, encourage better habits and generally improve well-being.

iTriage: With more than 8 million downloads, iTriage (available for the iPhone and Android operating systems) is one of the most popular products in the emerging mobile health -- or mHealth -- market. It's a combination of a symptom tracker (with information reviewed by Harvard Medical School) and a virtual yellow pages, directing users to nearby doctors, hospitals, pharmacies and more. The top searches each December are for upper-respiratory infections and depression.

Juice: The self-proclaimed "World's Funnest Energy Tracker" really is fun. The cartoony interface helps keep tabs on your sleep, exercise and nutrition. Were you an "awful" eater today? Tap the plate of junk food. Daily tips aim to boost results over time (free, for the iPhone).

GetHealth: With a concept inspired by Foursquare, this app lets you "check into" healthy behaviors. Your actions translate into "Munch," "Move" and "Mind" points, weighted based on your current health. Use those numbers to compete with friends (free, iPhone and Android).

Weight Watchers 360: The diet program's mobile app for iPhone and Android is designed to be a constant companion. Not only does it track food (with the help of a bar code scanner and a "Snap & Track" feature that lets you photograph a meal and assign a point value later), but it also focuses on your environment, said Catherine Ulrich, senior vice president of A "Spaces" function considers where you are (home, traveling, etc.) and your options, and offers "Panic Moment" advice. "Routines" helps you commit to small steps, such as eating breakfast.