I puchased the mi band last month , it works fine counting your calories and steps and also your heart beat but kindly not assume that results are 100? correct.because it counts more steps than you actualy walk and some time less heart beat than actualy you feel.so please check the results periodly .please also arrange the screen gard for this .my watch get scrated and it is 100% water proof.Its sleep monitoring is very usedul for everyone.