My Fitbit won the prize for being the only hardware/software to blue screen my Windows computer in at least a decade. It actually took me a few hours to figure out what was happening because I never suspected simply plugging in that device could do it. Sure enough, after 5 minutes or less it would hard crash my computer. I promptly gave it away and will never buy another one. I read some Amazon reviews where people talked about being on their 8th Fitbit and decided they have a real problem.