Data is collected from a ms band. Each folder is corresponding with a device. 
For each device, 6 sensors are sampled.. The format of each line is: 

Phone_timestamp,VALUE,Band_timestamp

+ Phone_timestamp is timestamp at that the phone received the data
+ Band_timestamp is timestamp at that the band sampled the data
+ VALUE is the value of sensor, it depends on type of sensor.

For accelerometer,m/s^2
 VALUE = AccelerationX,AccelerationY,AccelerationZ
For calories
 VALUE = Calories
For distance, unit are: cm,cm/s,ms/m,pedometer mode
 VALUE = Distance,Speed,Pace,Motion type
For gyroscope (degree/sec)
 VALUE = AccelerationX,AccelerationY,AccelerationZ,Angular AccelerationX,Angular AccelerationY,Angular AccelerationZ
For hear rate: number of beats per minute
 VALUE = Heart rate,Quality
For pedometer
 VALUE = #steps

For activity file, the format is:
Activity type,start time, end time