I've had this for a couple of months now and am wearing it every day. I started by using it to track my activity and establish a baseline. I am now challenging myself to increase activity a little every week. I set my own targets rather than using the default settings. I haven't used it to monitor food intake as I mainly cook from scratch so the barcode recognition didn't work and inputting ingredients individually was too much hassle. I'm not using the sleep tracking either as I found it uncomfortable to wear at night. I have not reason to believe that these functions would not work though if someone wanted to use them. The strap has stayed fastened during all activities. I ordered some cheap, extra straps online but don't think they will be as good as this one. Had online support from Fitbit when setting up my device. It works with my Samsung Core Prime even though that isn't on the list of compatible phones. Very pleased with my purchase. Would recommend.