The front facing cameras are on the top side on the cellphones. When using it for video chatting, a person is looking at the screen to see the face of the person on the other side. Now, the camera is on the top and this person appears to be looking down to the other person. So both the people are looking at the faces of each in a “looking down” posture.
The eye-to-eye contact experience is missing and that’s why video chat with cellphone cameras is still not that popular.
The position of the camera needs to be somewhere from within the screen to make it a true good experience.