https://techcrunch.com/2023/10/25/apple-watchs-best-new-feature-is-now-live/

With today’s watchOS 10.1 drop, Apple Watch Series 9 and Apple Watch Ultra 2 owners now have access to the smartwatches’ most exciting feature. Double Tap, which adds gesture-based interactions through tapping one’s index finger and thumbs together twice. It’s a clever new way to interact with the wearable when your other hand if full. It was easily the highlight of an otherwise modest update to the line.

I had a few days with a beta version of the feature during my Apple Watch Series 9 and Ultra 2 test period, and can confirm it largely works as advertised (I tend to wear my watch quite high up on my wrist, but after a small adjustment, it worked just fine). The feature was initially made available to beta testers earlier this month, and is now there for anyone with the compatible hardware.