A few simple buttons and a high-resolution touchscreen make it easy to learn and use iPhone.
Locking iPhone and Turning It On or Off
When you’re not using iPhone but you still want to receive calls and text messages, you can lock it.
When iPhone is locked, nothing happens if you touch the screen. You can still listen to music and adjust the volume, and use the button on the included stereo headset to play or pause a song, or answer or end a call.
By default, if you don’t touch the screen for a minute, iPhone locks automatically.
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