By default, StandBy mode is turned on in iOS 17.

Ifit's not, or should you want to turn off the feature, open upSettings> scroll down toStandBy> and switch the activation toggle.

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There are two other settings within this page for turning on Night Mode, which shifts the color tint from vibrant to red when the environment is darker, and notifications. 

With the latter setting, you can have critical notifications displayed in StandBy mode, and you can also tap on them to expand to the preview, similar to the iPhone's lock screen behavior.

StandBy mode works with any compatible iPhone that's charging and rotated to a horizontal orientation. You can power the iPhone with a MagSafe charging dock, a standard Qi-enabled wireless charging pad, or even a standard lightning cable.

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StandBy mode will automatically turn on when both requirements are met, and your iPhone lock screen will change into a widescreen status hub with the time, date, and temperature.

One notable advantage when using a MagSafe-certified charging dock is location awareness. If you plan on docking your iPhone on multiple MagSafe accessories -- say you have one for your work desk, one by your bedside, and another for the kitchen -- the iPhone will automatically display the StandBy mode configuration you set for each.

Swiping sideways on a docked iPhone cycles between three StandBy mode panels:

• The first panel displays two columns of interactive widgets, similar to those on the iPhone home screen. A tap and hold on this panel allows you to add or remove widgets, move them around, and turn on Smart Rotate and Widget Suggestions for a more personalized experience.
• The second panel is a photo clock, displaying the time and your choice of existing photo albums or photo categories (i.e., pets, nature, people). A tap and hold on this panel allows you to select the pictures you want to display.
• The third panel shows a larger clock with different styles to choose from.

If Show Notificationsis turned on in the iPhone's StandBy settings, incoming messages and alerts will appear when the device is docked. 

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For more privacy, you can toggle on Show Preview on Tap Only, so that you have to unlock the device via Touch ID or Face ID to view the notification in full.