how do you like your fitbit?
I love it. It helps me keep track of my activity levels and gives me inside on my heart health. 
i think the heart rate tracking on it is very useful
Yes it comes in handy for people who have issues with their heart and with the new technology it is able to measure abnormalities. 
do you have one of the new models? they have done a good job of catching up to the apple watch
Yes I have the sense which is one of the newer models. I like Fitbit because the price is affordable for the quality of product and user friendly for both apple and android. 
how long does the charge last?
Mine on average last about 2.5 days. 
oh wow that is a long time
Yes I tend to take it off at night though so I don’t use the sleep function as much it maybe shorter if you use it all day and night.