You can tell your iPhone 3GS what you want it to do with your voice. Here’s how.
1. Press and hold the Home button below the screen for 2 seconds until you hear a beep.
2. To call a person, say on of the following:
- Call John Doe
- Call John Doe home
- Call John Doe mobile
- Call 5555555555
To play music, say:
- Play
- Play Music
then you can say:
- Pause
- Next Song
- Previous Song
- Play Green Day
- Genius
- Shuffle
Source: iPhone User Guide
