Apple’s iPhone allows you to put the device to sleep when it’s going to be inactive. Furthermore, you can awaken it from Sleep mode by setting an alarm. The first case allows you to set a time that shuts down running apps and places the phone in a state of “standby,” saving battery life. When you set the alarm, the phone will also come out of this state of sleep and allow you to start up applications again. Writer Bio

How to Turn an iPhone Off   On at a Specified Time - 52