Mobile phones are a cozy home for apps with a range of functions, from calling for a ride to recording diet and exercise histories.

To evaluate the effectiveness of using a weight loss app, researchers conducted a meta-analysis of 14 studies (described in the journal Obesity) including 2,129 people, average age 58.4 years, with type 2 diabetes. Participants who used a mobile app significantly reduced their body weight and decreased their waist circumference, but not their body mass index. People with obesity and those who used the app along with other behavioral interventions experienced the best improvements.