More and more people are using their phone to track their sleep habits. Getting a good night's sleep used to be a challenge for Sarah Collier, but the 42 year old says once she started monitoring her sleep with her fit bit six years ago, she's had more restful nights. Now a new study from NYU School of Medicine looks at using popular phone apps that track sleep. Dr. Rebecca Robbins is the author of the study which also shows men are more likely than women to track their sleep. The most popular apps for sleep tracking in the study were fit bit, lose it and apple health. She says she's now averaging a good 8 hours of sleep a night. Dr. Robbins cautions more study is needed to see how effectively apps measure sleep and how those measurements can be used to gauge changes in sleep patterns.