The thickness number is the headline. But it's the fourth or fifth most remarkable thing about this device.
Summary
- Multiple credible sources confirm Apple's first foldable iPhone — likely called iPhone Ultra, though Apple hasn't confirmed any name — will measure approximately 4.5mm when unfolded and 9mm to 9.5mm when folded, making it thinner than any current iPhone when open.
- The device uses a 7.76-inch inner OLED display and a 5.49-inch outer display, both with a 4:3 aspect ratio, powered by the A20 Pro chip on TSMC's 2nm process with 12GB RAM.
- Samsung Display developed a near-creaseless panel with a 0.15mm crease depth and under 2.5 degree crease angle specifically for this device — far below the visible crease on current foldables.
- Space constraints forced real trade-offs: no telephoto camera (just two 48MP sensors), Touch ID via power button instead of Face ID, and a possible absence of internal MagSafe magnets — with leaked cases suggesting Apple may offload that function to a case accessory.
- Mass production, originally planned for June 2026, has been pushed to August. A September launch alongside the iPhone 18 Pro remains the target, but early supply will be tight. Starting price is expected above $2,000.
"At 4.5mm unfolded, the iPhone Ultra would be thinner than the iPhone Air, thinner than the 13-inch iPad Pro, and thinner than any iPhone Apple has ever sold. That's not a spec tweak — that's a structural statement about what Apple thinks a foldable should feel like."
The Thinness Number in Context
The 13-inch iPad Pro is Apple's thinnest current product at 5.1mm. The iPhone Air — Apple's recent slim-focused phone — sits at 5.6mm. At 4.5mm unfolded, the iPhone Ultra would be thinner than both. It would be thinner than most slab phones on the market. In a foldable. That's not an incremental design achievement. That's a different category of engineering.
The camera bump is the honest asterisk here. Case schematics show a protruding square camera plateau that adds roughly 4.5mm at its highest point, pushing the maximum local thickness to around 9mm at the lens. The body is genuinely 4.5mm. The back isn't flat. Both things are true simultaneously.
What Apple Sacrificed to Get There
This is where it gets interesting. A 4.5mm unfolded chassis doesn't leave room for everything. Face ID requires a TrueDepth camera array that simply won't fit. Apple is using Touch ID in the power button instead — the same approach used on iPads. The telephoto camera is gone. Two 48MP sensors handle main and ultra-wide. The internal magnet ring for MagSafe may also be absent, based on dummy unit analysis that shows no magnets where they'd normally sit. Cases with magnets are already in production. Apple may be moving MagSafe outside the phone entirely.
These aren't failures. They're deliberate choices. Each one bought back a fraction of the thickness that enabled the 4.5mm target.
The Crease Problem Apple Solved
Every foldable phone has a crease. Most are visible in direct light. Samsung's Galaxy Z Fold 7 crease is the current best-in-class, and it's still noticeable. The panel Samsung Display developed for the iPhone Ultra targets a 0.15mm crease depth — significantly lower than anything currently shipping. A crease angle under 2.5 degrees means the display surface is nearly flat even at the fold point. For Apple, shipping a foldable with a visible crease would have been unacceptable. The near-creaseless display is arguably the most technically difficult part of this entire product.
September Target, August Production, Real Risk
Mass production has slipped from June to August. That leaves a tight window for a September launch alongside the iPhone 18 Pro models. Ming-Chi Kuo flagged supply shortages potentially extending into 2027. If you plan to buy one at launch, treat it like an early Vision Pro situation — limited stock, high demand, and a wait list that forms on announcement day.
Loading
