When the Apple Watch launched, it was unclear if smartwatches would pan out. Ten years later, Apple has a $100 billion hit that reshaped the watch industry and ushered in a new age of fitness tracking.

Here's a look back at the turning point that made the Apple Watch into a powerful health tool and what's kept it relevant in the face of competitors for a decade.

On the Apple Watch's 10th birthday, this concept of boundary-less-ness still holds. Eight years after the iPhone's debut, Apple created a device that blended into the wearer's life, with technology that tracked steps,