It is a latest software which includes better sleep tracking technology along with running and fitness feature 

Users  can see how long there're in each sleep stage .Users will see sleep stage date on Apple watch in sleep App.

New running metrics and hart rate zones included in to the workout app so you can track how  efficiently you run.

 In health app users can manage their medication ,vitamins and supplement and also set up schedules and reminder and view information on their medication.

Users can use new siri interface in watch OS9

WatchOS9 will also include new watch faces including an astronomy face and the lunar calender.