Apple's iOS includes advanced power-management features that help extend the iPhone's battery life. One feature turns off, or puts to sleep, the iPhone's screen after a certain period of time. Some activities, such as watching a video, automatically disable this behavior. For other uses, you must manually disable the Auto-Lock setting to keep your iPhone from sleeping.

Warning

• The information in this article applies to iOS 6. It may vary slightly or significantly with other versions or products.