Automatic Screen Locking You can change the length of time before sleep in the "General" tab of the Settings app. Tap "Auto-Lock" and pick a time between one and five minutes, or select "Never."
Can you make your iPhone turn off at a certain time?
The timer in the built-in Clock app on your iPhone and iPad has a feature called Stop Playing, which will automatically turn off any music, movie, TV show, or video clip that is currently playing. It's perfect for setting your entertainment to turn off at a specific time.