iPhone becomes very warm during WAZE usage

Should I be concerned about the buildup of heat in my iPhone? I am wondering what is causing that heat buildup.

It’s the same on my Android. It gets positively hot. Can’t be good for the phone’s components or functioning.

If you do a search for “iphone warm hot” and you’ll find a couple other threads about this where it is discussed. In general, it’s because of multiple simultaneous and extended antenna usage.