HTC DROID Incredible - Manual (Page 69)

Phone calls 9
Not all mobile networks support conference calling. Contact Verizon
Wireless for details.
Muting the microphone during a call
On the screen, tap to toggle between turning the microphone on
or off. When the microphone is turned off, the Mute icon ( ) appears
in the status bar.
Turning the speakerphone on or off during a call
On the screen, tap to toggle between turning the speakerphone
on or off. The Speakerphone icon ( ) appears in the status bar when
the speakerphone is on.
To avoid damage to your hearing, do not hold your phone against
your ear when the speakerphone is turned on.
Ending a call
On the screen, tap End call.
If the phone display is off, press POWER to turn on the screen so you
can tap End call.
If the phone number of the person who called is not in your contacts
list, you can choose to save the number to your contacts list after you
hang up.