One of the new features in iPhone OS 3.0 is “Voice Memos” -How To use- , a native app that can record, play & share what you say!!
Let’s run the application…

As above, sees a big microphone is on the center of screen and there is a  VU meter below. Try touching the microphone! VU meter peak LED turns on!!!
now touch the iPhone‘s microphone!! nothing happens!!
What was wrong?!
Yes This is a Touch sensitive microphone!