If you have an iPhone 4 or are in an area without adequate Internet service, you can still instruct your iPhone to do simple tasks with Voice Control. Voice Control doesn't work if Siri is turned on; to turn Siri off, tap Settings→General→Siri→Off. Here's how to use Voice Control:
Press and hold the Home button, the center button on the earphones, or the button on your Bluetooth headset, until the Voice Control screen opens.
The words that appear on the Voice Control screen are suggestions for commands you can give.
Two quick beeps let you know that Voice Control is ready to listen to your command.
Speak the name of the person you want to call (or the artist you want to hear).
Voice Control replies with the name it understood. If it found more than one match, it reads off a list of the options. Repeat the option you want.
If you asked for music, iPhone responds with “Playing songs by artist's or album name,” and begins playing.
Repeat the option that you want.
iPhone dials that person.
If Voice Control offers an option you don't want, say “No” or “Cancel.” Voice Control closes and you have to start over.