Fitbit Force vs. Fitbit Flex: Head

LiveScience.comFitbit Force vs. Fitbit Flex: Head-to-Head Fitness Tracker ComparisonLiveScience.comThe Fitbit Force and the Fitbit Flex are two of the fitness trackers — which measure your daily amounts of exercise, calories consumed and sleep — available this holiday season, but how do they stack up against each other? The Force, which is the ...