As far as fitness bands/trackers go, shelling out 10k for one is not something I'd ever remotely consider. However, after getting a Xiaomi Mi4 and loving it so far I considered the Mi Band which came at a mere Tk. 1300 in the Gadget Gang 7 year end sale. 

First off, the build quality is pretty good as things are kept simple with an elliptical tracking module that slips into the band snugly. With an IP67 rating, it should be pretty waterproof to the point where you can wash your hands with it or even take showers but let's not test our valuable gadgets that way. The biggest plus of the band is that after a day of keeping it on, you will barely feel it on your wrist. The charge lasting for 30 days is a blessing. 

The Mi Band app is what you use to track your daily steps (goals) and sleep. I found the step-tracking to be somewhat inaccurate as it counted rickshaw rides as well. Good for cyclists, I guess? I didn't get the Mi band for being a glorified pedometer. The sleep tracking is where it's at. It automatically detects when you sleep and wake up pretty accurately. The alarm feature in the app wakes you up when you're in a light sleep cycle within half an hour before your alarm setting. The band vibrates along with your phone's alarm. Pretty nifty. 

If you have a  Xiaomi phone, you can use the smart unlock feature to have the phone automatically unlock when you are wearing the band. 

All in all, the Xiaomi Mi Band is a  decent fitness tracker for its price and can help you with sleep. Anything for good sleep, man.