Fitbit is an American company in san Franciso known for its product of same name which are activity trackers, wireless enable that measure quality of sleep, step walked etc. It has found that the use of similar device result in less weight loss rather than more. It has released many product among them fitbit charge 2 is one of best product for people.
The product is very expensive as normal people cannot afford it. It has little bit side effect for our intenal body. It has lot of feature with good looking All day activity and auto sleeping tracking let’s you see how your whole routine adds up. It gives an accurate heart beat rate, and fat burning statics.
So, I recommend you friend to use only after the research.