WatchOS 2 Arrives As Apple Watch Sales ExpandWatchOS 2 Arrives As Apple Watch Sales Expand

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Apple made watchOS 2 available for download this week after a delay of several days. The improved operating system brings native apps to the watch, which frees up the wearable from the iPhone to a certain degree.

Apple initially announced plans to release watchOS 2 on Sept. 16, the same day it distributed iOS 9. At the last minute, the company said it found a bug and needed more time to properly resolve it. It promised to make the operating system available "shortly," and Apple has done exactly that. The delay lasted only five days, which is nothing much to complain about.

With watchOS 2 installed, owners of the Apple Watch will be happy to know their apps can run independently, without a nearby iPhone. In watchOS 1, apps on the watch were mirroring logic operations taking place on the iPhone. Now, all the calculations are managed on the wearable itself.

The benefit here should be improved app performance; apps should open and run quicker.

WatchOS 2 adds several other features, including one called Time Travel. Using the Digital Crown, Watch owners can scroll forward and backward through their calendar to see future and past appointments. Nightstand Mode turns the Watch into a bedside alarm clock. Activation Lock prevents the Apple Watch from being wiped by a thief. Siri can now record individual workouts, and third-party apps can now tap into health data. Transit directions are available in Transit Maps for select US cities.

Last, Apple Pay on the Watch adds support for store-branded credit cards and loyalty cards.

The expanded feature set is sure to make the device more powerful and more useful in owner's daily lives.

[Read why Apple Watch owners are so satisfied.]

This week also marks an expansion of Apple Watch availability.

Best Buy today announced that the Apple Watch is now in stock at all its stores in the US. The company has a limited selection of the watches on hand, but sells a broader range of them via its website.

Carriers are getting in on the action, too. Sprint will begin selling the Apple Watch on Sept. 25 (the same day the iPhone 6s and 6s Plus go on sale).

"We believe Apple Watch will be one of the hottest gifts for the holiday shopping season," Sprint CEO Marcelo Claure wrote in a statement. "We are excited to offer Apple Watch at hundreds of our stores alongside iPhone 6s and iPhone 6s Plus." The Watch will be available when Sprint stores open at 8 a.m. on Friday, Sept. 25.

T-Mobile will add the Apple Watch to its store shelves on Friday, too.