New watchOS is loaded with new features, though none seem to be earth shattering. I updated my Apple Watch late last week (I always give a new release a couple of days to settle down before I download) and have experienced no problems. Nor have I found any significant (though Apple says version 3 is up to 70 time faster) performance improvements [8, 12]. Apple has promised improved performance with this release, but I have not used any Apps yet that reflect that. I do agree that Apps do load much faster than before.
Some New Features:
- Breathe App added to health and fitness
- Heart Rate App added
- Home App – for HomeKit connected devices added
- Emergency one-touch calling by holding the side button [5, 6] – This is set up through the Apple Watch App on your iPhone
- Sharing of health and fitness progress 
- Watch faces manage by Watch App on iPhone [5, 10, 12, 13]
- Use scribbled handwritten responses to messages 
- Improved Reminders App with Siri integration 
- Digital Crown – double-click to return to last App, Single-click to return to the home screen; turning the crown uses Time Travel, zooms, scrolls 
What are the significant changes I see?
- Glances are gone, control center added 
- Dock for frequently used Apps – Used this a couple of times, but for me it is not a major change [5, 10, 12]
- Ability to unlock Mac running Sierra – I hope to use this everyday as soon as I get Sierra installed [5, 12]
Should You Upgrade?
At this point I say that you should definitely upgrade! Operation of the watch is snappier so that alone is worth it.
How to Upgrade
First, upgrade your iPhone to iOS 10. When that has been completed, place your watch in the charging cradle (it needs to already be at least 50% charged). The iPhone and Apple Watch should be in close proximity for the software download by Bluetooth. On the iPhone go to Apple Watch App >> My Watch >> General >> Software Update [8, 9, 10]. This will begin the 561MB update. It took me about 90 minutes when I updated my Apple Watch, but I have heard that the update for some users took much longer.
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