Most fitness trackers also track sleep, but reviewers say the Jawbone UP (Est. $130) is a standout for its unique ability to spot an ideal waking moment based on your REM cycles. It also features a power-nap switch that analyzes your sleep habits to determine what your best nap length is -- and then wakes you with a silent alarm.
According to Paul Sawers of tech website TheNextWeb.com, the sleep-tracking feature "covers all facets of your time in bed, including hours slept, time to fall asleep, phases of sleep (deep versus light) and overall quality." Its clever alarm can sense your lightest phase of sleep and wakes you within 30 minutes of your set alarm time to reduce grogginess. Christina Tynan-Wood with Family Circle also gives it two thumbs up for "the ability to set an alert to vibrate when you've been idle too long."
In addition to its in-depth sleep tracking, the Jawbone UP is a favorite among reviewers for its superb fitness app, which is compatible with iPhone and Android devices. Clara Moskowitz with LiveScience.com says the site "provides rich and useful data, it's easy to find the information you're looking for in the app, and it allows you to scan food barcodes to input nutrition information." The app turns your activities into games by linking your data with your friends', encouraging friendly competition. A unique log lets you input "how you feel after you've had time to digest your meal … to establish how different foods affect your mind and body," says Paul Sawers. Clara Moskowitz finds the Jawbone UP offers more information overall to help you interpret your own fitness data and gives the UP extra points for its fun daily health tips.
Where the UP falters is when it comes to accessing the data. There's no built-in screen, so users must remove the bracelet and plug it into their device to upload measurements and read daily counts. Many say this time-consuming chore reduces the convenience of the band and can hamper motivation because there's no instant feedback.
Still, for some people, sleep tracking is their top priority, and the Jawbone UP is phenomenal at analyzing the subtle gradations of the sleep cycle. That, combined with its great fitness app, makes the Jawbone UP the logical choice for those who are serious about sleep.