I am using this device from about 1 month
Pros
The battery backup of the phone is so great more than 2 month easily
The alerts feature if u get a call after 3 sec your band starts vibrate
The tracking system is very accurate not like other bands it just work good
Waterproof
Cons
No heart rate sensor
The app for this band doesn’t store data of previous days so can’t check what you have done previously