At its World Wide Developers Conference this week, Apple introduced several updates to the health and fitness features on the Apple Watch that will come with the launch of the new WatchOS: a new emergency alert feature called SOS, some updates to the device's Activity app, and a new meditation app called Breathe.

Breathe is an app that walks users through short deep-breathing exercises. Users can set a timer and have their Watch remind them to breathe at particular times of day, which makes the ubiquity of the Watch an asset. The app can also guide users through breathing exercises using only haptic feedback if they don't want to look at their screen.

"Simple things like the activity ring can be powerful in helping people change behavior, but we know there’s more to health then fitness," Apple Director of Health and Fitness Technologies Jay Blahnik said in the keynote. "So with WatchOS we’re launching a new app for health. It’s called Breathe and it’s designed to guide you through simple deep-breathing sessions that can help you quiet your mind, relax your body, and better deal with everyday stress."

Another feature, SOS, will turn the Watch into a sort of a combined personal emergency response device and medical bracelet, allowing the wearer to contact emergency services and then displaying their emergency medical information on the screen afterwards. It also alerts emergency contacts to the user's location and situation.

"You push the side button to activate it. It’s going to let you know it’s calling 911, and then you’re going to be on a live call with emergency services from your Watch," Apple VP of Technology Kevin Lynch explained. "And this works as either a cellular call via your iPhone or directly from the Watch if you're connected to WiFi. And after you’re done talking to emergency services, the Watch will automatically notify your emergency contacts. It will send them a map of where you are. And after sending the message, your Watch will now show your medical ID, which is also a new feature. It has things like your age, and allergies, and other information you might want to put there."

SOS works all over the world, and knows what the emergency number is -- so in Hong Kong, for example, it would dial 999 instead of 911.

Lynch and Blahnik both announced a number of updates to the Activity app. Perhaps most notable is that the company has added a social aspect to activity tracking, allowing users to share not just their activity rings, but more granular data as well, with other Watch users they know. They also introduced three new Watch faces that integrate the activity rings directly into them, allowing those who use the Apple Watch primarily for fitness to see their progress at a glance without having to open an app.

Finally, Blahnik revealed that with the new WatchOS, one group that might previously have found the "Stand" ring awkward (at best), will now have a special version of the app geared toward them. Apple worked with nonprofits the Challenge Experts Foundation and the Lake Shore Foundation to develop algorithms that can track meaningful activity metrics for wheelchair users.

"Now wheelchair users will have a setting," Blahnik said. "The 'Time to Stand' notifications will be changed to 'Time to Roll', there will be two workouts specifically dedicated to wheelchair users, and the activity rings will be optimized for wheelchair pushes."