The iPhone has generally taken a very straightforward approach to handling alerts, eschewing complicated schedule and profile setups in favour of a simple hardware Ring/Silent switch, a practice also somewhat followed with the iPad. The idea here is simple: Leave the switch in the “ring” position when you want to hear sounds and move it to the “silent” position when you want alerts to either vibrate or make no sound at all. Unfortunately, while easy this approach has had its limitations: Even in “silent’ mode your iPhone will vibrate in most cases, and the screen will light up when notifications and alerts come in.
In iOS 6 Apple has addressed this by creating a true “Do Not Disturb” feature that can be toggled on demand and/or set to a daily schedule. At its most basic, turning on Do Not Disturb is simply a matter of going into your iPhone Settings app and toggling the option found there. When enabled, your device will suppress all alert notifications—sounds, vibrations and screen illumination—whenever the screen is already off; calls will be sent directly and quietly to voicemail and notification messages will stack up on the lock screen without waking up your device’s screen.
By taking a quick trip into your Settings app and selecting Notifications, Do Not Disturb, you can also configure your iPhone to automatically enable this mode based on a daily schedule and determine which phone calls will still be permitted to ring through.
Note that alarms set in the Clock app will still sound even when Do Not Disturb is enabled. Also, notifications and phone calls are handled normally when you’re actually using your device (i.e. if the screen is on), regardless of the Do Not Disturb setting.