If you've updated to iOS 14, here's a new feature for the iPhone you may want to check out: Back Tap. As the article below explains, you can set your iPhone to enable several functions by two or three taps on the back of the phone.
I've looked at the feature on my iPhone, but haven't decided yet what function I'd like the taps to enable. Ah, a weighty decision.
Jim Hamm
https://www.yahoo.com/news/hidden-iphone-feature-launching-fall-200708155.html