iPhone 8 could launch with Apple Watch 3 on the side
https://www.cnet.com/news/apple-watch-3-iphone-8-event-september/
Since the launch of the company's original Watch and its Watch Series 2 successor last year, Apple has fallen behind other companies in the wearables market. With this new upgrade and cellular connectivity, this could boost the Apple Watch's popularity and get people excited about it again.
An Apple Watch with cellular connectivity would mean you could stream music without an iPhone.