Does the Apple phone use one earpiece for phone calls and video chats?

Generally cell phones have two earpieces, one on top of the phone screen and one on the phone's speaker.

When you make a phone call, the earpiece on the screen is used when the phone is not on speakerphone, while the speakerphone is used when the phone is hands-free.

Video chatting generally does not have a handset mode, but is basically a speaker mode, which is used in addition to the phone screen above the other handset.