Turn It Into a One-Press Voice Memo Recorder

If you collect ideas throughout the day, or you like to quickly record stuff, this is one of the best ways to use your Action button. You can assign the button to a Shortcut that opens Voice Memos and starts recording automatically, which is way faster than opening the app or using your Control Center. 

That makes it a great idea for writers, students, journalists, and anyone who thinks better out loud than on a keyboard. Also, if you tend to forget what people tell you a lot, this can help you remember it when you really need it.