The iPhone is a cell phone and multimedia device made by Apple. It lets you make and receive phone calls, listen to music and play games. If you are in a crowded area, you may want to turn up the volume on the iPhone to hear phone conversations or music more clearly.
Turn up the volume by pressing down on the "Volume up" button on the left side of the iPhone. An indicator will appear on the face of the phone.
Slide the "Ring/Silent" switch toward the face of the phone. This button is above the volume toggle on the left side of the phone and controls whether the phone plays all sounds or does not ring, play alerts or sound effects. When this switch is set toward the face of the phone, it plays all sounds.
Press the "+" button on the wire on the iPhone headphones. This button controls the volume of the iPhone when you are using the headphones. If the iPhone is in your pocket, this button might be more accessible than the others.