Neat, practical design ; 7-day battery life ; Excellent online interface ; Limited range of features ; Expensive

No GPS

The set-up process is fairly routine. Enter all your relevant personal data (including height and weight of course) and you’re off and running. One thing to note, however, is that there is no instructions with the unit regarding downloading the...

Simple design ; Easy to use ; Clean, intuitive website

New features are mostly gimmicks ; Expensive for what it is ; Only really counts steps

Fitbit is as easy to use as ever, but the features added to the second generation are too gimmicky to help justify that $100 price tag.

Compact ; lightweight design ; Impressive sleep tracking ; Great app support

Manual food tracking ; Not waterproof ; No GPS

Data minutiae can be enthralling ; Turns your fitness regimen into a game ; Accurately track stairs climbed

Easy to lose — no way to remotely locate ; Gimmicky "motivation" feature ; Fitbit.com navigation can be confusing

An allure that stems from simultaneously playing the voyeur and exhibitionist roles of my own life

Small, light, and easy to carry, the Fitbit Ultra effortlessly tracks your basic daily activity level. It has a host of online analytical tools, it tracks sleep quality, and it boasts both Android and iOS mobile apps.

The Fitbit Ultra needs to be within 15 feet to sync with its USB-connected base station. The Trainer feature and a deeper activity data analysis cost extra. It's not waterproof.

The Ultra extends Fitbit's already impressive personal fitness data measurement abilities, but for the same $99.95 price. Already a high-tech pedometer, the Ultra now has an altimeter to record stairs climbed, too. It isn't as advanced as more...