Samsung Galaxy S6 - Options During a Call

55 Make and Answer Calls Calling
Multitask While on a Call
If you exit the call screen and return to a Homescreen, your active call
is indicated by Callon the Status bar.
This lets you continue with your current call and do something else,
such as access the contacts list, view a recent email, or locate a
picture.
To return to the call screen:
► Drag the Status bar down to display the Notication panel, and
then tap Callnotication.
To end a call from any application:
► Drag the Status bar down to display the Notication panel, and
then tap
End call.
Options During a Call
Your phone provides several options that you can use during a call.
Adjust the Call Volume
► Press the Volume keys to increase or decrease the volume.
– or –
Tap Extra volume to quickly add more volume to the incoming
audio.