By double-tapping with your thumb and index finger at the same time, you can answer or end calls, play or pause music, and more. This article explains how to use Double-Tap, which models support it, and how to get a similar feature on older Apple Watch models.
How to use double tap on Apple Watch | Apple Support
Double-tap is enabled by default in watchOS 10.1, so no setup is required. To use the Apple Watch double-tap gesture, follow these steps:
Quickly tap the hand of your watch twice with your thumb and index finger together.
The actions that Double Tap can perform include:
