iPhone Duo Review: It’s Not the Next iPhone. (Video)

For nine years, you've used every iPhone the same way, by swiping. The iPhone Duo, Apple's first foldable, changes that for only the second time, and it's the first time Apple rebuilt the hardware to do it. After a week with it, the Duo has a spot in my pocket. So does my Pro Max.

Apple's lineup has always worked like a ladder, from the iPhone 17e up to the 18 Pro Max, each rung the same phone with more on top. The $2,000 Duo sits off to the side, next to the iPhone Air. Think of it as a folding iPad that makes phone calls.

The hinge holds the whole idea together. I've tested every foldable sold in the US, and this is the best hinge I've used. It holds any angle you set, and it's precise enough that a game called Duometry asks you to open the phone to, say, 74 degrees and then scores your guess. The crease shows up in photos and video. In your hand, you have to hunt for it. The IP68 rating means I still take it into the shower for podcasts.

Closed, you get a passport-shaped 5.4-inch screen that felt cramped after eight years of Pro Max phones, partly because iOS 27 parks navigation on the right edge and shoves everything left. Open it and the 7.6-inch nano-texture panel is 50 percent larger than the 18 Pro Max's screen, with 120Hz ProMotion. It looks great indoors and out. You get real split view for the first time on an iPhone (Mail beside Safari, say) with a floating video on top and the keyboard still up. Instagram, Threads, and Facebook were optimized before launch. YouTube and TikTok aren't optimized yet. Fold-aware games like Duometry and Piano Duo make it feel like a little handheld console.

The trade-offs start at unlock. There's no Face ID. Touch ID lives in the power button, and even with three fingers registered it kept asking me to scan again, which is a bad first step every time you pick up a $2,000 phone. Siri AI took about five days to index the phone and has felt slower to me since public release. Lots of MagSafe accessories, including Apple's own wallet, don't fit the shorter body.

The camera is the biggest trade. You get a 48-megapixel main camera and the same 48-megapixel ultrawide as the 18 Pro, with no telephoto, so 2x is the limit for optical-quality shots. At a Doja Cat concert, the Duo blew out the highlights trying to catch her on stage from my seat, while the 18 Pro in my other hand got great shots. Everyday photos are fine. Duo Preview is the clever part. You take selfies with the rear camera, and your subject can check the framing on the outer screen. Skip the under-display camera inside for photos. Apple calls it the FaceTime camera for a reason.

Battery life held up. I never topped up midday all week, including that concert, with Siri still indexing and my portable charger left at home.

If you mostly watch, read, and work side by side, nothing Apple makes beats the Duo. If your phone is your camera, keep the Pro or Pro Max. I'm in a smaller third group. iPhone Handoff lets one phone number live on two iPhones, so my Pro Max shoots and the Duo handles everything else. After nine years of swiping, the Duo asks you to learn a hinge, and for anyone who'd rather read and watch than shoot, that's a fair trade for a telephoto lens.