I used till the Fitbit Zip my spouse. Wearing the tracker really motivates me to walk more, do more exercise I who have a very sedentary job (less than 1000 steps per day on a working 10 hours a day). So I ordered my Fitbit One's promo on Amazon and the price of almost Zip. I wanted to analyze my most nights since I have a very incomplete sleep. Overall I am very satisfied with the tracker that I never left, except when necessary to recharge the (once every 15 days) but I'm pretty disappointed with the very incomplete party night: two mode are proposed: I sleep for the first 95% of my night, which is a very good sleep, for the second mode I do not sleep that 50% of my nights. Reality must be between the two, but without more precision. Also, no table does really lets analyze the quality of his sleep according to physical activity and of the main parameters influencing the night (Night at home or elsewhere, alone or in pairs, having to eat late, drank the alcohol later, watching screens later smoking later, due to the exercise later ... etc all these factors that are known to influence sleep) So there has to perform updates for sleep can really be analyzed!