The App: Rise

($50 per month; Rise.US)
How it Works:
You're paired with an actual nutritionist who monitors what you eat (you can log meals manually and snap pictures of your plate) and provides daily advice through an in-app messaging system.

Road Test:
"I've wanted to lose weight for a long time, but while I have the exercise part figured out, eating right is a problem. I chose a nutritionist who offered tough love but could also be laid-back. She praised my choice of steel-cut oats for breakfast, but recommended I add Greek yogurt when she noticed I wasn't getting enough protein. Knowing that someone was monitoring me kept me accountable. I thought twice before making unhealthy decisions, like eating fast food. I plan to keep up with Rise. When you compare it with the cost of meeting with a nutritionist in person, it's totally worth it."—Kristi Stewart, Special Projects Manager
Zestar Diet Pilot

The App: Zestar Diet Pilot

($4 per month; ZestarDietPilot.com)
How it Works:
Zestar generates daily meal plans based on your food preferences and health goals. If you stray from the plan, the app's algorithm will adjust your next meal to make up for it.

Road Test:
"I wasn't looking to lose weight, but I wanted to eat better so I could stop feeling so sluggish all the time. On the days I followed Zestar's menu, I definitely felt fuller and less tired. I used to eat just a granola bar for breakfast, but the app suggested proteins like peanut butter or scrambled egg whites. When I had the extra protein, I didn't experience my typical midday energy crash. When I didn't have enough in the morning, the app added more protein to later meals. I eventually drifted from the plan, but I learned that I wasn't eating nearly enough protein to power me through the day."—Liz Chan, Digital Editions Designer
Noom Coach: Weight Loss

The App: Noom Coach: Weight Loss

($10 per month; Noom.com)
How it Works:
As you track your food intake, the app labels filling, low-cal choices in green and calorically dense ones in red. And thanks to its "intelligent coaching" function, informative articles pop up on your news feed based in part on what you've eaten.

Road Test:
"When it comes to weight loss, my greatest challenge is staying on track, so I liked that I could set regular reminders to log meals. It motivated me in other ways, too: Encouraging messages like 'Abs are made in the kitchen,' would appear on my home screen daily. You can also chat with others through the app's message boards. We'd swap meal ideas and virtually high-five one another when we made healthy choices. I plan to keep using it. Knowing people are supporting me helps prevent me from giving in to cravings."—Arianna Davis, Associate Editor