Two features that are often found on smart watches are:
Fitness monitoring and Multiple time zones
Most smart watches has fitness monitoring such as: heartbeat monitoring - the watch can determine if the user has a normal or too rapid heart beats while he or she is wearing the watch and on his or her activities. Watches also has distance monitoring, like how many steps you did and how far did you run or walk today.
It has multiple time zones. Some watches are exported from different countries to different locations. Time and regions has different time zones that's why it is necessary. Sometimes, when you set a time zone, languages are automatic as well.