Apple just shipped its thinnest flat iPhone, the iPhone Air. Still, a foldable iPhone due next year could make that milestone feel temporary. Early leaks point to a device that is markedly slimmer when you open it, and noticeably chunkier when you close it. That contrast is the Fold’s defining move.
How thin are we talking
Analyst reports put the unfolded iPhone Fold around 4.5 to 4.8 millimeters thick. That would beat the iPhone Air’s 5.64 millimeters, making the Fold about a fifth thinner when you use it.
Compare the family in plain numbers:
- iPhone 17: 7.95 mm.
- iPhone Air: 5.64 mm.
- iPhone 17 Pro / Pro Max: 8.75 mm.
- iPhone Fold (unfolded): 4.5–4.8 mm.
- iPhone Fold (folded): 9–9.5 mm.
These figures come from recent supply chain and analyst reports. You can see why the unfolded Fold looks like a radical design move.
What that feels like in your hand and pocket
Open the Fold and you get one of the thinnest large screens Apple could make. The device should feel almost impossibly slim while you browse, watch, or type. Close it and the phone’s thickness will jump into the same territory as Apple’s Pro models. That makes the Fold a compromise between pocket carry and on-screen presence.
Tradeoffs Apple is likely accepting
Thinning the chassis costs space for components. Analysts expect Apple to skip some hardware features you see on other iPhones, in favor of the slimmer profile. Ming-Chi Kuo says Face ID is unlikely in the Fold’s thin frame, and Apple may use side-button Touch ID or other solutions instead. Expect higher pricing too; industry reports peg the Fold well above $2,000.
Quick takeaway for buyers
If you value the biggest screen in the thinnest package, the Fold promises a new kind of tradeoff you can feel every time you open and close the device. If you prefer simple, compact pocket carry and full-feature parity with existing Pro models, the Fold will ask you to accept compromises for its thinner open profile. Decide which matters more to you: pocket comfort or screen scale.
Bottom line: the Fold aims to change how Apple balances thinness and function. It will not replace the Air. It will make you rethink what “thin” means for a phone with a folding display.
