Occasionally, I have found that my iPhone or iTouch will not "wake up". It's in sleep mode but doesn't respond to any of the buttons or touching the screen. It does also happen, on rare occasions, that the device will just freeze completely while in use. So what to do in this situation? If it was an iMac, we'd just pull the plug. If it was some other device we might remove the batteries and replace them. In this case, we have no access to the battery and there is no "plug" to pull.
What you need to do is perform a hard reset of the device. What this does is effectively disconnect the electrical supply internally for a few seconds, causing the device to switch off completely.
To perform a hard reset, you simply hold down the Power button and the Home button at the same time for 10 seconds. Then wait a few seconds and press the Power button to start the device up again. You should see the familiar Apple logo appear. If you don't, try another hard reset. If you still get nothing on the screen, either you battery is completely flat or you have a more serious problem with your device.
If you need help diagnosing or resolving iPhone, iPad, iPod Touch or Mac problems, why not click on over to our main site MacHelpline.net and see what we can do to help!