Many Fitbit reviews comment on features such as its waterproof status, battery life, the charging process, its tracking and measurement accuracy, and the online interface that accompanies the wearable device. Fitbit sells several models, including the One, Flex, Blaze, Charge and Surge.
Reviewers at CNET.com praise Fitbit devices for their slim styling; compatibility with iPhones, Android and Windows phones; the ability to use them with many third-party fitness apps; the sleep tracking/alarm function; and the standard five-day battery life. CNET reviewers were less impressed with the non-waterproof nature of some models, such as the Charge HR, the difficulty in reading heart rate at a glance, the short length of time the display remains on, and the non-intuitive goal setting functions.
TopTenReviews.com appreciate the Flex's light weight and that its bands come in two sizes and a variety of colors. The review site was displeased with the five-day battery life, noting that many competing fitness trackers have longer-lasting batteries.
Wired magazine cites the battery life as a selling point for the Fitbit devices, and hail how easy it is to sync the device to a phone, tablet or computer. Wired's reviewer also found the step- and sleep-tracking functions to be highly accurate. The devices were marked down for not all being waterproof, for the brightness of the display in darkened environments, and the reviewer's experience of discomfort with the clasp on the band when wearing it for long periods.