The Apple iPhone is a smart phone that was introduced in 2007, with three other models appearing since then. The overall design and function of the phone has remained the same. The iPhone 3 added GPS and the ability to utilise a 3G connection. The iPhone 3Gs included the ability to shoot video. The iPhone 4 features an updated chassis that is a bit more angular, and the ability to make video calls. The speaker is adjusted in the same way on all models.
Check that your iPhone is turned on by pressing the round button on the bottom of the face of the phone.
Unlock the phone by sliding your finger across the slider at the bottom of the screen.
Adjust the volume of your iPhone by depressing the volume button on the left edge of the phone, close to the top. This will cause a volume indicator to appear, superimposed over the other icons on your screen. This will increase the volume of your ringer. If you wish to adjust the volume of the phone speaker, use this button during a live phone call. You can also control the volume of your speaker when you are using your iPhone as a music player in the same manner.