Apple Watch is smooth but there might come a situation where an app on Apple Watch become unresponsive. In such case you must know how to force quit/close app on Apple Watch to take your Apple watch to normal state.
You can force close app on Apple Watch just like you do on iPhone. On iPhone you can long press the Power Button and then Home Button to clear RAM and refresh the app (Check How to Reset RAM on iPhone/iPad).
How to Force Quit App on Apple Watch running watchOS 4
Step 1: Press & Hold the Side Button
Step 2: When you see the shutdown screen, release the Side/Power Button
Step 3: Now Press & Hold the Digital Crown.
That is all! The app will immediately close.
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