How to use StandBy on iPhone Duo

StandBy on iPhone Duo works without a charger. Apple's iPhone Duo announcement says the phone enters StandBy on either the outer or inner display when you set it down, even when it isn't charging, and describes it as a photo frame, widget hub and clock.

That is the big change from earlier iPhones. On other models, Apple's StandBy guide for iOS says StandBy starts when the locked phone is charging and set on its side.

What StandBy is on iPhone Duo

StandBy first arrived with iOS 17 as a way to turn a charging iPhone placed horizontally into a smart display, 9to5Mac notes. Apple put it plainly in its launch announcement: "StandBy gets a major upgrade on iPhone Duo."

Per that announcement, new Calendar and Weather faces join the existing Clock and Modular faces, and every face gets more colors, fonts and complications. Apple's guide lists the customization options as style, font and color, widgets, photos, clock position and appearance, depending on the face.

Which screen and which position?

Apple's guide says to lock iPhone Duo, partially fold it like a book or a tent, and set it down. Apple's Pose iPhone Duo page spells out the screens: fold it like a book and the inner display faces you in landscape, or set it down like a tent and the outer display faces you in landscape. Apple lists both postures for StandBy.

Macworld's Jason Cross wrote on launch day that in tent posture "it becomes a nice little smart clock for your desk," and that a book-style fold shows a two-page StandBy view. Apple hasn't published a list of exact hinge angles that trigger StandBy. The positions themselves are a choice in Settings > StandBy, covered in the steps. For more on the folded postures, see tent and laptop modes.

Always-On and Night Mode

Apple's iPhone Duo specs list an Always-On display for both displays. Apple's guide says the Always-On display keeps StandBy visible on supported models, while other models wake StandBy with a tap, a nudge of the table or Siri. Based on the spec page, it appears the Duo falls in the first group, though Apple's guide doesn't name the Duo in that sentence.

Night Mode, per Apple's guide, dims the screen in low light and adds a red tint. Apple pitches StandBy as a bedside clock, and Night Mode is likely the setting that makes that work in a dark bedroom.

Faces: clocks, photos, widgets and more

On iPhone Duo, Apple's guide says you tap the current face and then swipe left or right to pick another one. MacRumors adds in its how-to that some faces also accept swipes up or down to change content.

The Modular face holds widgets, and Apple says Smart Rotate changes those widgets through the day while Widget Suggestions picks them based on your usage. The Photos face has a Select option to change which photos appear or how often they shuffle. If you want ideas for what to put on that widget face, see the best widgets for two screens.

Battery: the catch with no charger

MacRumors warns that StandBy can drain the battery and suggests turning on Only While Charging if that bothers you. Apple hasn't said how much battery StandBy uses per hour on iPhone Duo.

If you do charge in StandBy, Apple's guide says StandBy remembers your preferred view for each MagSafe charging spot, so the kitchen charger can show photos while the nightstand shows a clock. Apple's specs list MagSafe and Qi2 wireless charging up to 25W. For charger picks, see the best MagSafe chargers, and for charging speeds, the iPhone Duo charging guide. Apple's own MagSafe Charger, which its spec page names for the Duo, comes without a power adapter.

Coming to other iPhones in iOS 27.3

MacRumors reports that iOS 27.3 brings the Duo's StandBy features, including the updated clock faces and new Calendar and Weather faces, to iPhone 11 and newer. As of Nov 11, 2026, iOS 27.3 is in developer beta, and Apple says it will reach the public in December, according to MacRumors. MacRumors notes that on iPhone Duo, StandBy also works folded like a book or a tent without a charger, and that feature isn't in its list of iOS 27.3 additions for other iPhones. More on the beta: iOS 27.3.

A leak reported by 9to5Mac in September pointed to five more unannounced faces in iOS code, including Home Camera and Home Modular. Apple hasn't announced those faces, so treat them as unconfirmed.

Bottom line

On paper, StandBy on iPhone Duo starts when you lock it, fold it partway and set it down, no stand or cable required. The trade-off is battery, so Only While Charging is worth a look if you leave the Duo propped up for hours. We'll update this guide when iOS 27.3 ships. Which face are you using on your nightstand?

More on setup: first settings to change on iPhone Duo.