I often use the iPhone's built-in alarm to wake me up from short naps, or to let me know when a parking meter is going to expire. The other night, though, I discovered another use for it. As I was preparing to go to sleep, I really wanted to listen to some music as I read and, inevitably, fell asleep with my book crashing to the floor next to me. What I didn't want, though, was for my iPhone to play music all night and wear the battery down by morning. Looking through the device's iPod settings, I couldn't find anything that would allow me to tell it to stop playing music after a set period. Then I realized the alarm might be just the ticket. Within the Clock app, where one set's the alarm, there are options for the alert you wish the alarm to make. There's the buzzer, the xylophone and dozens of others. At the bottom of the list, however, is the setting that solved my problem: "Sleep iPod."
By selecting this option and then setting the alarm, the phone will automatically shut off playing music after the set time. Voila!
